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Asahi Pentax K-1000 Service Manual

1. REMOVE FOUR PENTAPRISM FRAME SCREWS Next take out the four screws holding the pentaprism SnD OPT Our COMM AAE EREN frame Fig 77 Lift out the complete exposure meter assembly se ASSEMBLY the assembly which includes the pentaprism frame the exposure meter circuit board and the speed resistor REASSEMBLY Before replacing the exposure meter 3 assembly check the positions of the two wires which 8 pass through the camera body hole Fig 78 The black 2 wire is the one you unsold red from the exposure meter circuit board the gray wire is the one you un soldered from the hot shoe terminal Make sure that both wires sit within the recessed area _ of the body casting Fig 78 If the wires sit above the raised section of the body casting they ll be crushed by the galvanometer as you replace the exposure meter assembly kas 4 Also notice the three adjustment setscrews in Fig 78 The USING SCREEN i i i ENT SETSCREWS spring loaded focusing screen sits on top of these setscrews oie N You can see the focusing screen tray at the bottom of the pentaprism frame Fig 79 in Fig 79 we ve removed the exposure meter assembly with the pentaprism still in place Try pushing up the focusing screen tray Fig 79 you ll then feel the spring tension When you replace the pentaprism frame the focusing screen tray sits on top of the setscrews The setscrews then push up the focusing screen tray toward the pentaprism So the se
2. the two screws shown in Fig 63 hold the pentaprism to the pentaprism frame The two screws allow a shifting adjustment for the penta prism By loosening one screw and tightening the other you can shift the pentaprism laterally That s another adjustment you don t want to disturb Fortunately there s a technique you can use to remove the pentaprism without disturbing the lateral position Loosen just one of the pentaprism retaining screws Then lift out the pentaprism When you replace the pentaprism tighten only the screw which you loosened A strip of porous plastic around the bottom of the penta prism seals the focusing sereen from dust But as with any SLR cleaning the focusing screen is a common job You can now see the focusing screen and the galvanometer needle F 64 Notice in Fig 64 that two screws hold the galvanometer to the pentaprism frame Both screws are sealed with red lacquer When you see red lacquer used as a locking agent you can be pretty sure that the screw holds a critical adjustment In the Spotmatic the adjustment controls the zero posi tion of the needle With no power to the circ the needle should center in the focusing screen mask Fig 64 What if it doesn t You can then loosen the two screws Fig 64 and shill the galvanometer housing Removing the pentaprism also allows you to see the three photocells on the photocell circuit board Fig 65 Remember the upper CdS cell Fig 6
3. Pentax K4OOO contents OPERATION AND FEATURES OTHER FEATURES OF THE K1000 REMOVING THE BOTTOM COVER REMOVING THE TOP COVER WHAT S NEXT THE K1000 EXPOSURE METER SYSTEM THE PHOTO SWITCH TROUBLESHOOTING THE K1000 EXPOSURE METER CHECKING THE GALVANOMETER CHECKING THE SPEED RESISTOR CHECKING THE DIAPHRAGM RESISTOR REMOVING THE EXPOSURE METER CIRCUIT BOARD REPLACING THE SPEED RESISTOR REMOVING THE DIAPHRAGM RESISTOR AND THE FRONT STANDARD REMOVING THE PENTAPRISM FRAME SHORTCUT TO REPLACING THE GALVANOMETER CALIBRATING THE EXPOSURE METER VARIATIONS ON THE K1000 METER REMOVING THE EXPOSURE METER ASSEMBLY AS A UNIT Section 1 INTRODUCTION Pentax Spoimatics have long been among the most popular of the 35mm SLRs Adding a built in cross coupled exposure meter turned the early Pentax SLRs into Spot matics Yet even the recent Spotmatic models use basically the same shutter and transport systems as do the early Pentax cameras Most of the variations you ll encounter among Pentax Spotmatics are in the exposure meter systems The original Spotmatics use stopped down metering and screw mount lenses But later models changed to full aperture metering and bayonet mount lenses Yet once past the exposure meter you ll find the familiar Pentax shutter and transport Even the fully automatic electronically controlled Spot matics the ES models retain the same basic shutter mechanism The ES just
4. s possible that the counter shaft gear Fig 137 won t engage properly when you replace the support shaft assembly Pentax also has an answer for this possible problem they supply two different types of support shaft assemblies That s why we ve indicated two different part numbers in Fig 137 REMOVING THE BRAKE LEVER In Fig 142 and Fig 143 you can get a little better look at the brake lever The brake spring pushes the brake lever toward the opening curtain wind gear Remember the brake adjustment screw limits how far the brake lever can move As the opening curtain wind gear moves from the cocked position Fig 143 to the released position Fig 142 it pushes aside the brake lever against the pressure of the brake spring LUG ON OPENING CURTAIN B WIND GEAR SCREW HOLDING TRANSPORT GEARS Figure 146 Transport latch The brake spring then provides the cushioning action for the opening curtain Notice the lubrication tube in Fig 143 Early Spotmatic models don t have this lubrication tube Later models added the lubrication tube to supply oil to the side of the brake lever and to the lug on the opening curtain wind gear Fig 143 The lubrication tube contains a string of felt material within a plastic sleeve As you can see in Fig 142 only the material extends beyond the end of the wind gear stop plate The material then comes against the lug on the opening curtain wind gear when the shutter is
5. Figure 82 Shutter Released Try watching the X sync contacts as you cock and release the shutter You can then locate the part which closes the X sync contacts Notice the insulated pin on the opening curtain latching cam Fig 81 The opening curtain latching cam attaches to the opening curtain wind gear the gear that winds the opening curtain With the shutter cocked the insulated pin moves away from the X sync contacts Fig 81 The X sync contacts now open But the opening curtain latching cam rotates as the open ing curtain crosses the focal plane aperture The insulated pin then strikes the back side of the X sync contacts Fig 82 Asa result the opening curtain latching cam closes the X sync con tacts to fire the flash With the shutter released Fig 82 the X sync contacts re main closed Wouldn t the flash then fire if you connected it to the flashcord terminal Initially that seems to be the case However there s another pair of contacts the FP sync con tacts serving as a safety switch Fig 83 Notice that the FP sync contacts are normally open Fig 83 The FP sync contacts close as the mirror moves to the tak ing position about the same time as the shutter releases So the FP sync contacts close before the X sync contacts close In Fig 84 you can see why the FP sync contacts must be closed before the X sync contacts can fire the flash With the FP sync contacts open the flashcord terminal doesn t have
6. Resistor R1 resistor R2 and the photo switch CdS cell form a voltage divider across the battery Normally there s a sufficient voltage drop across resistor R1 to keep the transistor turned on But as the light level decreases the resistance of the photo switch CdS cell increases Since more voltage then ap pears across the CdS cell there s a smaller voltage drop across RI At a low enough light level very little voltage appears across R1 too little to hold the transistor in conduction The transistor then switches off Turning off the transistor opens the current path to the exposure meter circuit But remember the light level must drop below EV2 at ASA 100 before the photo switch turns off the meter TROUBLESHOOTING THE K1000 EXPOSURE METER The schematics we ve been using for explanation purposes apply to several Spotmatic models which use basically the same exposure meter But you will encounter variations in the dif ferent models Fig 42 shows the actual schematic for the K1000 You ll notice in Fig 42 that the photocell section of the circuit is slightly more complex than in our simplified schematics Each of the two CdS cells has three leads Also notice that both the speed resistor J300 and the diaphragm resistor J400 have fixed resistors in series connections The fixed resistors are mounted underneath the exposure meter circuit board Most of the troubleshooting procedures we ll now discuss apply to the other Spot
7. diaphragm metering ring Fig 6 in a clockwise direction The resistance should increase smoothly When the diaphragm metering ring reaches the fully clockwise position you should read a resistance of around 150K If you read an open or if the resistance change appears erratic you ll have to remove the front standard to reach the diaphragm resistor We ll describe the procedure in a later topic But first let s say the diaphragm resistor checks proper ly Yet you still get the symptoms of a defective diaphragm resistor Checking the schematic Fig 42 should give you another clue as to the possible problem As with the speed resistor there s a fixed resistor connected in series with the diaphragm resistor Again the problem may be as simple as poor solder connections Fig 47 points out the lands for the fixed resistor Try retouching the solder connections on these two lands If retouching the solder connections doesn t correct the problem check the fixed resistor Just leave the black wire of the diaphragm resistor disconnected And measure the resistance between the two fixed resistor lands Fig 47 REMOVING THE EXPOSURE METER CIRCUIT BOARD As we indicated earlier it s unusual to have to replace the exposure meter circuit board However you ll have to pull aside the exposure meter circuit board for certain repairs First lift the rewind shaft to open the camera back Then note the position of the rewind shaft det
8. opening curtain wind gear If the shutter cocked indicator drags on the opening curtain wind gear the opening curtain may have an erratic movement Leave the shutter in the cocked position to complete the reassembly of the speed selector components Seat the retard rod in its lower bearing hole the bearing hole closer to the back of the camera Place the compression spring on the up per pivot of the retard rod Fig 206 Now seat the pallet rod in the bearing hole closer to the front of the camera remember to slip the spacer over the lower pivot before seating the pallet rod Place the pallet cam follower on the upper end of the pallet rod Fig 206 PUL HTC RSH ES ION The release cam you ll recall must Lubricate the two bearing sur cam Fi ig 207 with shutter oil Use sparingly you only want lubrication bearing sufaces Also make sure that you ve thoroughly cleaned the speed selector assembly a bearing hole which receives the release Place the brass collar over the larger pin on the opening curtain wind gear Then seat the release cam Fig 206 The rectangular slot in the release cam fits over the larger of the two pins on the opening curtain wind gear the pin which has the brass collar You can now see why we re replacing the release cam with the shutter in the cocked position The release cam then clears the end of the closing curtain latch Fig 206 In the shutter released position the closing
9. there s a second variable resistor which programs the diaphragm setting The diaphragm resistor is a large resistor ring behind the lens mount You can see the coupling to the diaphragm resistor after you remove the lens Just push in the lens latch Fig 1 Then rotate the lens a partial turn in a counterclockwise direction To replace the lens first locate the red dot on the bayonet mounting ring Fig 5 align this red dot with the red dot on the camera s lens mounting ring Fig 6 The lens should seat fully Now rotate the lens clockwise until you feel it latch in place Notice that the lens provides a special convenience feature a lens alignment dome Fig 1 The lens alignment dome helps you change lenses when you re shooting pictures at night Even though you can t see the alignment dots you can feel the positions of the lens alignment dome and the lens lat ch Fig 1 Just align the lens alignment dome with the lens latch to seat the lens Then turn the lens clockwise until it lat ches in place With the lens removed locate the tab on the diaphragm metering ring Fig 6 The tab couples to another tab at the back of the lens the diaphragm setting ring tab Fig 7 Try turning the diaphragm setting ring as you watch the diaphragm setting ring tab Notice that the diaphragm setting ring tab turns clockwise as you set smaller apertures it turns counterclockwise as you set larger apertures Consider now that the
10. you can shift the collar to reposition the upper pallet rod lever Make the pallet disengaging adjustment with the shutter released at the 1 15 second setting Now loosen the two setscrews Fig 115 Using your finger or a screwdriver blade push the lower pallet rod lever and the pallet control lever as far as they ll go to the right Fig 112 This movement disengages the pallet Continue holding the lower pallet rod lever and the pallet control lever Then rotate the pallet rod collar Fig 115 as far as it will go in a clockwise direction as seen from the top Tighten the two setscrews to lock the pallet rod in place REMOVING AND CLEANING THE SPEEDS ESCAPEMENT You ll normally want to remove the speeds escapement even for routine cleaning and lubrication Take out the two screws at the bottom of the body casting Fig 116 Then lift out the speeds escapement assembly In earlier Spotmatic models the tripod socket doesn t have the flat side Fig 116 The tripod socket then prevents you from reaching one of the speeds escapement screws So to remove the speeds escapement you must first take out the tripod socket You can now clean and lubricate the speeds escapement Clean the speeds escapement as a unit One way to clean the unit is to swish the speeds escapement through an alcohol bath Operate the speeds escapement a few times by pushing the first gear segment in a counterclockwise direction Then use an air blower t
11. CLOSING CURTAIN WINDING ROLLER SETSCREWS WHICH LOCK TENSION SETTING WORMS Figure 162 The tension setting worms will be loose once you let off the initial tensions LATCHING CLOSING CURTAII tue i WIND GEAR ES RETARD DRIVE LUG Figure 163 INSERT SCREWDRIVER THROUGH CLEARANCE CUTOUTS TO REMOVE SCREWS HOLDING LIGHT TRAP PLATE P SCREWS HOLDING SUPPORT PLATE Figure 166 Removing the closing curtain tension setting worm SCREWDRIVER SLOTTED ENDS OF TAKE UP ROLLERS Figure 167 There s one more part to get out of the way before you remove the curtains the light trap plate at the bottom of the body casting Fig 165 Remove the two screws Fig 165 and lift out the light trap plate REMOVING THE TAKE UP ROLLERS At this point there should be no initial tension on the take up rollers Fig 166 Now push the tension setting worms out of their body casting housings from right to left as seen in Fig 166 Both of the tension setting worms are identical So on reassembly it doesn t matter which tension setting worm you use for which curtain Both of the tension setting gears screw onto the ends of the take up rollers central shafts Also both tension setting gears have left hand threads However there s a trick to unscrewing the tension setting gears you must hold the cen tral shafts to keep them from turning At the top of the camera locate the upper ends of the en
12. CURTAIN TIMING DISASSEMBLY TO REMOVE THE CURTAINS REMOVING THE TAKE UP ROLLERS REMOVING THE WINDING ROLLERS REPLACING THE SHUTTER CURTAINS APPLYING THE INITIAL TENSIONS TIMING THE CURTAIN WIND GEARS REPLACING THE MIRROR RETURN GEAR AND THE WINDING ROLLER PINION REPLACING THE TRANSPORT GEARS REPLACING THE SPEED SELECTOR ASSEMBLY SETTING THE CURTAIN TENSIONS SHUTTER SPEEDS ADJUSTMENTS IN THE SPOTMATIC REMOVING THE WIND SHAFT AND TAKE UP SPOOL REPLACING THE SPROCKET IN THE K1000 Section 3 SPEED CONTROL SYSTEM In most respects the Pentax speed control system is representative of focal plane SLR s But the Pentax has one unique twist Most focal plane shutters use the closing curtain latch for the bulb function Not the Pentax the Pentax has a separate bulb lever Locate the closing curtain latch and the bulb lever at the front of the speed selector assembly Fig 106 The top section of the bulb lever serves as a cam follower it comes against the bulb cam Fig 106 At the bulb setting Fig 106 a cutout in the bulb cam faces the bulb lever Try pushing down the release shaft as you watch the bulb lever Notice how the bulb lever swings toward the bulb cam You can see how the release shaft controls the bulb lever in Fig 107 The tail of the bulb lever just rides against the release shaft When the release shaft moves down its groove allows the spring loaded bulb lever to rotate clockwise Pentax K1000 ae Fig
13. Fig 66 And unsolder the three galvanometer wires from the exposure meter circuit board It s not necessary to unsolder the wires coming from the photocell circuit board Instead just remove the two screws Fig 66 Then lift aside the photocell circuit board leaving its wires connected to the exposure meter circuit board Finally remove the four screws holding the pentaprism frame Fig 67 One of the screws is a little difficult to reach without removing the speed resistor Also notice that the pentaprism frame screw in the upper left hand corner Fig 67 is smaller than are the other three screws Lift out the pentaprism frame together with the galva nometer Fig 68 If your previous troubleshooting pinpointed an open coil you can now replace the galvanometer assembly Just remove the two sealed screws Fig 68 and slide out the galvanometer away from the pentaprism frame When you install the new galvanometer you must adjust the zero position of the needle Remember the needle should center in the focusing screen mask So before tightening the two screws shift the galvanometer housing until the needle centers Then hold the galvanometer in position as you tighten the two screws Fig 68 SHORTCUT TO REPLACING THE GALVANOMETER We ve described the procedure for completely removing the pentaprism frame However when you know you must replace the galvanometer there s a shortcut procedure you can use Check first to see
14. Pentax provides another adjustment technique to correct the linearity Pentax supplies three different versions of the release cam Fig 211 shows two of the three types the Type A cam and the Type B cam The difference between the shapes of the two release cams Fig 211 isn t too obvious However you can identify the Type B cam by the round hole Fig 211 There s no identi fication hole in the Type A cam Consider that your camera has the Type B cam But the 1 1000 second exposure is too slow Replacing the Type B cam with the Type A cam causes the closing curtain latch to disengage sooner As a result you get a faster shutter speed Again any adjustment you make on the release point of the closing curtain has its greatest effect at the fastest shutter speed You can then change the release cam to correct the 1 1000 second shutter speed Correct the 1 125 second shutter speed by adjusting the slit width setscrew Fig 210 The third type of release cam the Type C cam provides a faster shutter speed Fig 211 shows the position of the iden tification hole in the Type C cam If 1 1000 second exposure is too slow you can then use the Type C cam to bring in the fastest speed And again adjust the slit width setscrew for an accurate exposure at 1 125 second Once you ve checked and adjusted your slit width speeds telock the setscrew and locking collar with a locking agent such as red fingernail polish Then check the slow sp
15. Then tilt the mirror cage slightly forward as you lift it out of the camera REASSEMBLY When you replace the mirror cage make sure that the mirror latch is to the back of the release shaft extension arm Fig 96 Test the opera tion after you replace the tensioning lever spring Fig 90 MIRROR COCKING LEVER POST Once you ve checked the operation test the overtravel of the release shaft Slowly depress the release shaft until the shutter releases The mirror should release before the release shaft reaches the bottom of its travel You should then be able to push down the release shaft a slight distance further That s the overtravel If you don t have this overtravel you can use the sliding adjustment on the release shaft extension arm Just loosen the two screws Fig 96 Then slide down the extension arm to make the mirror release sooner slide up the extension arm to make the mirror release later OPERATION OF THE MIRROR CAGE With the mirror cage removed try cocking the shutter Then push down the release shaft What happens Nothing should happen the shutter should not release Why Remember in the SLR the mirror releases the shut ter So without the mirror cage there s nothing to release the opening curtain To operate the shutter you ll have to simulate the mirror cage operation Continue holding down the release shaft Then push the opening curtain latch Fig 97 toward the back of the camera The
16. You can now remove your spring retaining clip and test the operation The procedure we ve just described saves time because you don t have to rewind the return spring But what if the return spring does come loose You ll then have to reapply the initial tension Starting with the parts in the rest position Fig 128 wrap the return spring in a clockwise direction around the wind driver You can determine when you have the proper amount of initial tension by pulling the end of the return spring the end that connects to the driver stop plate toward the rewind end of the camera Pull the return spring tight to see how far the end reaches With the proper amount of initial tension the end of the return spring should reach to the middle of the camera body What if the return spring reaches further than this Then you don t have enough initial tension Continue to wind on the return spring checking the initial tension after each turn Now connect the end of the return spring to the driver stop plate The proper amount of initial tension is fairly critical If you don t have enough initial tension the spring coils will ex tend too far beyond the wind driver that could cause a bind Excessive initial tension results in a hard wind stroke SPRING LOADED PAWLS SPRING Loop TWO PIECE REDUCTION GEAR Figure 133 Starting position for replacing wind driver REMOVING THE SUPPORT SHAFT ASSEMBLY The support shaft assembl
17. adapts the Pentax shutter and transport systems for fully automatic shutter speed control That s why the K1000 provides a good representative for your thorough study You ll be servicing many variations of the same camera Also the K1000 is quite representative in several general categories It provides an excellent example of the double roller focal plane shutter the mirror operation of the single lens reflex and the electrically cross coupled exposure meter system SPEED KNOB RELEASE BUTTON lt gt lt p A Figure1 The K series of Spotmatics have bayonet mount lenses rather than screw mount lenses OPERATION AND FEATURES The Pentax K1000 Fig 1 provides full aperture metering with semiautomatic control The needle appears through the finder Fig 2 Just change the shutter speed or the f stop until the needle centers in the focusing screen mask You ve then set the camera controls for the proper exposure As you look through the finder try changing the light coming through the lens The needle should move up as you allow more light to pass through the lens to the focusing screen The needle should move down as you decrease the light Also try turning the speed knob Fig 3 as you look through the finder The needle should move up as you set slower shutter speeds it should move down as you set faster shutter speeds Changing the f stop by turning the diaphragm setting ring Fig 3 should again move the ne
18. at which you can use electronic flash The X sync contacts close when the opening curtain un covers the focal plane aperture At this time the closing cur tain must not be in the aperture the aperture has to be com pletely uncovered for electronic flash Although the K1000 has X sync contacts and FP sync contacts it only allows you to use the X sync contacts Why There s only one flashcord terminal on the camera Fig 1 This flashcord terminal connects to the X sync con tacts In other Spotmatic models you ll find two flashcord ter minals one for X sync and one for FP sync However few people use flashbulbs these days Since there s little need for FP synchronization Pentax lowered the cost of the camera by eliminating the FP flashcord terminal As you ll discover a lit tle later the FP sync contacts do serve a second purpose in the camera There s another part the K1000 has eliminated to reduce the selling price the self timer Most Spotmatic models have self timers As you ll see the K1000 has the space and coupling for the self timer mechanism But by leaving out the self timer feature Pentax could sell the same camera for a lower price The other camera features remain the same in the various Spotmatic models Even the very early Pentax SLR s provide the shutter cocked indicator When you cock the shutter a red section of the shutter cocked indicator shows through the top cover window Fig 9 the red flag se
19. before proceeding the speed knob and the wind lever Why Well you need these parts in place to make your tests and adjustments Many people try to get along without taking the time to replace the parts or to replace the parts Properly Yet they usually end up wasting time It takes too long to cock the shutter without the wind lever And it takes too long to set shutter speeds without the speed knob In Fig 32 we ve replaced the wind lever and the speed knob assembly Notice that we ve also replaced the three screws holding the bayonet retaining spring Actually the Figure 32 bayonet retaining spring will hold the wind lever you don t really have to replace the three screws There s one advantage though in replacing all three screws you can then keep the screws with the parts they hold After replacing the wind lever and speed knob try cocking the shutter Release the shutter by depressing the release shaft Fig 32 THE K1000 EXPOSURE METER SYSTEM You can now see most of the exposure meter system Fig 33 The wires from the speed resistor are twisted together passing over the top of the pentaprism These wires then con nect to the exposure meter circuit board Fig 33 The wires from the diaphragm resistor and the galvanometer also con nect to the exposure meter circuit board Early models of the Spotmatic obtain the center the needle principle by using a balanced bridge circuit the needle centers when t
20. can learn a lot about the camera just by observing the exposed parts And in many of the early Spotmatics this is as far as you ll have to go to cor rect one of the most common problems In the earlier Spotmatics the mirror catch lever has a slightly different shape Compare the mirror catch lever in the K1000 with an earlier design Fig 13 The notch in the earlier design engages the mirror tensioning lever in the K1000 the latching end of the mirror catch lever is flat The problem with the earlier style is that the mirror catch lever may not provide a secure latching action Bumping or jar ting the camera can sometimes disengage the mirror catch lever from the mirror tensioning lever The customer then brings you a jammed camera a camera that will neither cock nor release Fig 14 shows what you ll see after removing the bottom cover The mirror catch lever is in the shutter cocked position But the mirror tensioning lever has returned to the shutter released position What s happened here The owner has jarred the camera with the shutter in the cocked position As a result the mirror tensioning lever has jumped out of engagement with the mirror catch lever Now there s no spring tension to drive the mirror to the taking position Consequently the shutter won t release You can correct the problem fairly easily Just remove the E ring holding the mirror catch lever Then lift the mirror catch lever high enough
21. cleaning job at this stage of disassembly you won t be able to reach all the lubrication points When lubricating a focal plane shutter you don t need step by step lubrication points if you keep this general rule in mind Use shutter oil to lubricate parts which move during the release travel of the curtains e Use shutter grease to lubricate parts which do not move during the curtain release cycle e Use shutter grease to lubricate latching parts When the curtains move in the release direction they carry some parts with them These parts must not have a grease lubrication grease will cause erratic curtain movement So on parts such as the opening curtain wind gear and the closing curtain wind gear you want shutter oil Place a drop of oil be tween the gears and their bearing surfaces But be careful that you don t get any oil on the gear teeth Use an oil lubricant for the bearing surfaces of the curtain rollers As mentioned earlier the Pentax K1000 uses teflon bearings for the winding rollers Place a tiny drop of oil at the points where the pinion shafts pass through these bearings Also use shutter oil to lubricate the bearing surfaces between the take up rollers and their central shafts The transport gears in Pentax cameras provide exceptions to our general rules Although the upper transport gear spins with the opening curtain you should leave the bearing surface dry Oil on the large bearing surface could cause er
22. curtain latch While watching the action from the front of the shutter you can see the closing curtain creep toward the aperture The closing curtain is now pushing its way past the retarding action of the speeds escapement Just before the closing curtain reaches the aperture though it s released by the speeds escapement The closing curtain then fires across the aperture to complete the exposure Right now it s a little difficult to see exactly how the speeds escapement holds back the closing curtain But the up per retard rod lever Fig 111 engages a lug on the closing curtain wind gear As the closing curtain wind gear turns it pushes the upper retard rod lever toward the back of the camera The upper retard rod lever then turns the retard rod in a clockwise direction as seen from the top But the speeds escapement resists this clockwise movement Why Because the lower retard rod lever couples to a fork in the first gear seg ment of the speeds escapement Fig 112 The length of the ex posure depends on how long it takes for the closing curtain wind gear to push its way past the upper retard rod lever Besides being able to rotate clockwise or counterclockwise the retard rod can move up and down compression spring Fig 111 pushes down the retard rod The upper retard rod lever is then in the path of the closing curtain wind gear But consider what happens when you cock the shutter The closing curtain wind gear rota
23. curtain latch tends to sneak underneath the release cam Seating the speed selector assembly is the delicate part of the reassembly Start the speed selector assembly into place by feeding its center hole over the release cam shaft Next seat the speed selector far enough to pass the retard rod through the hole in the slow speed coupler Fig 208 You ll also have to help the pallet rod into place make sure the upper pallet rod pivot passes through the bearing hole in the speed selector plate Then replace the three screws and test the operation SETTING THE CURTAIN TENSIONS Replace the speeds escapement before adjusting the cur tain tensions You can then set the curtain tensions and adjust the shutter speeds with one trip to the test equipment Accurately setting the curtains tensions does require special test equipment equipment that will measure the curtain travel times With a focal plane shutter the two cur tains should travel at very close to the same speed And if they don t Then the exposure won t be uniform from one side of the aperture to the other That s why manufacturers give you curtain travel times how long it should take for the curtains to travel from one side of the aperture to the other You can adjust the shutter speeds without knowing the manufacturer s travel time specification But you ll find that the shutter speeds come in much more easi ly if you first set the proper curtain travel
24. down aperture Pushing up the stop down slide Fig 72 stops down the lens lt simultaneously throws an internal switch to disconnect the diaphragm resistor from the circuit Fig 73 shows the por tion of the schematic that includes the stop down switch the rest of the schematic is identical to the one you ve already studied With the stop down switch in the solid line position Fig 73 the diaphragm resistor connects to the galvanometer that s the full aperture position Pushing up the stop down slide Fig 72 then moves the stop down switch to the dashed line position Fig 73 In the dashed line position the stop down switch discon nects the diaphragm resistor from the galvanometer So the diaphragm resistor has no effect on the reading How then does the meter know your diaphragm setting Since you re tak ing your reading through the taking aperture the f stop setting affects the resistance of the CdS photocells Notice in Fig 73 that you have one additional adjustment In the dashed line position the stop down switch connects a variable resistor between the photo switch transistor and the galvanometer The variable resistor allows you to adjust the meter s accuracy in the stopped down mode Fig 74 shows the variable resistor in the popular Spot matic F The exposure meter circuit board should look VARIABLE RESISTOR FOR STOPPED DOWN ADJUSTMENT Figure 74 Exposure meter circuit board in Spotmatic F The galvanom
25. gears with nearly every shutter repair in a Spotmatic or in earlier Pentax SLR s You can remove the transport gears with the shutter in the released position Fig 144 as you ll later see you must reassemble the transport gears with the shutter in the cocked position Remove the screw the one with the teflon sleeve that holds the transport gears Fig 144 Now lift out the retaining disc Fig 144 Notice in Fig 144 that the slot in the retaining disc faces the front of the camera The slot provides clearance for the transport latch With the retaining disc removed you can see how the transport latch couples the two transport gears together Notice the step in the transport latch Fig 145 the step faces the front of the camera Right now the step in the transport latch is level with the edge of the upper transport gear slot Fig 145 The lower end of the transport latch fits within a slot in the lower transport gear So as the lower transport gear rotates counterclockwise it carries the transport latch in the same direction And the side of the transport latch comes against the upper transport gear The transport latch then drives the upper transport gear in a counterclockwise direction As you ve seen the upper transport gear turns the opening curtain wind gear to advance the curtains But the curtains can t release until you disengage the up per transport gear from the lower transport gear The lower transport gear c
26. hold the parts at the new position the counter dial ratchet pawl drops into a tooth slot in the counter advance pinion Opening the camera back allows the spring loaded reset lever Fig 138 to push the counter coupling lever in a clockwise direction The counter coupling lever carries the counter advance gear So as the counter coupling lever swings clockwise the counter advance pinion disengages from the counter shaft gear The spring loaded counter shaft then returns the counter dial to the starting position If your counter advance parts stayed in position you can remove them at this time Disconnect and remove the ratchet pawl spring Then lift out the shoulder spacer The small shoulder of the spacer fits through the counter dial ratchet pawl the large shoulder provides the retainer for the ratchet pawl spring Lift out the counter dial ratchet pawl and the washer which sits on top of the counter coupling lever Then lift out the counter coupling lever REASSEMBLY Place the counter coupling lever over the shoulder post Fig 139 Seat the washer on top of the counter coupling lever and place th counter dial ratchet pawl on top of the washer Now seat the ratchet pawl spring on top of the counter dial ratchet pawl The bent end of the spring goes down and rests against the body casting Leave the other end of the spring disconnected for now Fig 140 Seat the shoulder spacer through the spring and counter dial ratchet pa
27. if you want to move the bar closer to the edge of the focal plane aperture turn the closing curtain winding roller counterclockwise if you want to move the bar further from the edge of the focal plane aperture LEAD EDGE OF CLOSING CURTAIN BAR ALIGNED WITH SCRIBE MARK Figure 180 Figure 178 Rotate the closing curtain winding roller to wind on the closing curtain When the closing curtain bar aligns with its scribe mark seat the closing curtain wind gear as shown here LUBRICATE a ING CURTAIN POST WITH LUBRICATE WITH CLOSII SHUTTER OIL i WINDING ROLLER SHUTTER wR PINION LATCHING END OF CLOSING CURTAIN LATCH Figure 179 LUBRICATE BEARING SURFACES WITH SHUTTER OIL OPENING CURTAIN WIND GEAR PIN ON OPENING CURTAIN WIND GEAR LUG ON CLOSING CURTAIN WIND GEAR Once you ve timed the closing curtain wind gear you can lift out the closing curtain latch The closing curtain latch just gets in your way when you re installing the opening curtain wind gear Removing the closing curtain latch should allow the clos ing curtain to move across the aperture But you ll probably find that the closing curtain won t release Or it ll just move part way across the aperture The reason is that the opening curtain has moved too far in the release direction As a result the opening curtain binds the closing curtain Try rotating the opening curtain winding roller slightly in a counterclo
28. if the focusing screen needs cleaning If it doesn t leave the pentaprism in place Also leave the photocell circuit board installed Unsolder four wires from the exposure meter circuit board the three galvanometer wires Fig 46 and the black wire that goes to the negative battery terminal Fig 50 Lift aside the exposure meter circuit board by taking out its two screws Next remove the four screws holding the pentaprism frame Fig 67 You can now lift the pentaprism frame high enough to slide out the galvanometer Remove the two galvanometer screws Then slide the galvanometer out of the pentaprism frame Figure 70 CALIBRATING THE EXPOSURE METER Spotmatic models using the type of exposure meter described here as opposed to the earlier balanced bridge design have two variable resistor adjustments Fig 69 The two variable resistors provide adjustments for the linearity of the response J209 Fig 69 connects in series with both photocells So it s a high light adjustment The other variable resistor J210 connects in series with just one of the photocells J210 then provides a low light adjustment You can see the connections of the variable resistors in Fig 42 However Pentax regards the variable resistors as factory adjustments Unless the meter has a linearity problem you should not have to disturb the variable resistors But you can make a total response adjustment by adding a calibration resistor t
29. in the released position Fig 142 It comes against the side of the brake lever when the shutter is in the cocked position Fig 143 You can lubricate the mechanism by stacy a drop of shutter oil in the other end of the tube the end which wraps around the long screwhead The material within the tube stores the oil It then feeds the oil as needed to the proper places To remove the brake lever first disconnect the brake spring One end of the brake spring hooks to a screw holding the wind gear stop plate Fig 143 the other end hooks to the side of the brake lever Disconnect the brake spring from the screwhead Then lift out the brake spring Remove the brake screw Fig 143 and lift out the brake lever Watch for a loose washer under the brake lever the washer sits between the brake lever and the body casting REMOVING THE TRANSPORT GEARS For a routine shutter cleaning you should remove the transport gears Since the upper transport gear turns with the opening curtain it must be very clean Any dirt or lubrication in the upper transport gear will cause erratic curtain move ment The timing of the transport gears is also critical In a later topic we ll go through the reassembly timing and test pro cedures However you may wish to skip ahead to the topic Replacing the Transport Gears and perform the reassembly steps after removing the transport gears This practice will be helpful you ll be timing the transport
30. is less than 0 2mm you don t have sufficient overtravel A larger space gap means there s too much overtravel You can adjust the overtravel by repositioning the wind gear stop plate Fig 122 Locate the stop plate positioning Screw in Fig 122 this setscrew determines the position of the wind gear stop plate To make an adjustment first loosen the two screws holding the wind gear stop plate Then turn the stop plate positioning screw from the back of the camera Fig 123 The end of the stop plate positioning screw shown in Fig 123 should be sealed with red lacquer Se Turn the stop plate positioning screw clockwise to decrease the space gap The stop plate positioning screw then pushes the wind gear stop plate closer to the lug on the opening curtain wind gear To increase the space gap turn the stop plate positioning screw counterclockwise Fig 123 Then hold the wind gear stop plate Fig 122 against the stop plate positioning screw And tighten the two screws holding the wind gear stop plate ADJUSTING THE CURTAIN BRAKE Locate the brake lever in Fig 122 The brake lever pro vides a cushioning action for the curtains As the opening curtain wind gear nears the released position its lug must push PIN THAT ACTUATES SHUTTER COCI KED INDICATOR CLOSING CURTAIN LATCH WIND GEAR STOP PLATE STOP PLATE POSITIONING SCREW Figure 122 Shutter cocked Figure 123 END OF BRAKE ADJUSTMENT SCREW PLATE
31. latching lug on the top of the closing curtain gear couples to a pin on the bottom of the opening curtain wind gear So as the opening curtain wind gear rotates to the cocked position it carries the closing curtain wind gear in the same direction When you release the shutter the closing curtain latch engages the latching lug Fig 163 that s how the closing curtain latch holds back the closing curtain The release cam which you ve already removed disengages the closing curtain latch according to the distance that the opening curtain has traveled How about the lower lug on the closing curtain wind gear It s the retard drive lug Fig 163 The retard drive lug pushes aside the upper retard rod lever at the slow speeds The pin on the closing curtain wind gear Fig 163 serves to disengage the pallet after the exposure Once the closing cur tain has crossed the aperture the pin strikes the upper pallet rod lever The closing curtain wind gear then drives the pallet out of engagement with the star wheel You can now lift out the closing curtain wind gear Dur ing reassembly we ll point out the lubrication points But before applying any lubrication make sure you thoroughly clean the bearing surfaces Clean both of the curtain wind gears Also clean the bearing surfaces for the curtain wind gears the outside surface Fig 164 for the closing curtain wind gear and the inside surface for the opening curtain wind gear PINION FOR
32. match at least within 5 Here again some test instruments display the exposures at the two sides of the aperture simultaneously others require separate tests At this point you aren t so concerned about the accuracy of the 1 1000 second shutter speed You just want the same ex posure all the way across the aperture Continue to adjust the closing curtain travel time until the exposure at the opening side of the aperture matches the exposure at the closing side If the exposure at the closing side is slower than the exposure at the opening side add tension to the closing curtain take up roller If the exposure at the closing side is faster than the exposure at the opening side let off tension from the closing curtain take up roller Once you ve adjusted the travel times and set the side to side uniformity you re ready to adjust the accuracy of the shutter speeds TRAVEL TIME Edge to edge 34mm Distance 32mm Distance CLOSING cURTAIN TENSIOI B ADJUSTMENT Figure 209 Turn the tension setting worms clockwise to add tension counterclockwise to let off tension HOLE HERE RELEASE CAMS Type C Fastest Type A Type B Slowest SHUTTER SPEEDS ADJUSTMENTS IN THE SPOTMATIC With the curtains set for the proper travel times your shutter speeds should be quite close But you may now have to make minor adjustments to the closing curtain latch and to the slow speed coupler First check the fas
33. other end hooks to the mirror lifting lever So if you re holding the mirror tensioning lever toward the front of the mirror cage the mirror lifting spring tries to actuate the mirror lifting lever However the mirror lifting lever can t as yet move it s held by the mirror latch Fig 99 Continue to hold the mirror tensioning lever toward the front of the mirror cage Fig 99 normally the mirror catch lever Fig 88 holds the mirror tensioning lever Now simulate the action of the release shaft push down the end of the mirror latch Fig 99 The mirror should then move to the taking position A downward projecting roller on the upper end of the mirror lifting lever comes against the lifting lever link Fig 100 And the lifting lever link comes against a roller on the mirror bracket So the lifting lever link drives the mirror to the taking position Also observe the action of the opening curtain striker Fig 100 The striker link couples the opening curtain striker to the mirror lifting lever As the mirror lifting lever drives the mirror to the taking position the striker link pulls the opening curtain striker in a counterclockwise direction The upper end of the opening curtain striker then swings toward the back of the mirror cage to release the opening curtain Notice that you must continue holding the mirror tensioning lever toward the front of the mirror cage If you release the mirror tensioning lever the mirror r
34. release plate first You can then test the operation quickly and easily without worrying about the shutter cocked indicator However you can certain ly reverse the disassembly and reassembly sequence if you find it makes matters easier SCREW HOLDING N bz p SHUTTER COCKED INDICATOR a COCKED KE INDICATOR ge SPRING FOR SHUTTER COCKED h INDICATOR DISCONNECT THIS END OF SPRING Figure 124 TEFLON SLEEVE ON TRANSPORT GEAR SCREW RELEASE SHAFT Figure 127 Figure 126 SCREWS HOLDING DRIVER STOP PLATE RETURN SPRING pa hR SCREWS HOLDING DRIVER STOP PLATE REMOVING THE WIND DRIVER Take off the wind lever You can then see the coils of the clocktype return spring that s the spring which returns the wind driver and the wind lever after the cocking cycle Fig 128 The return spring rotates the wind driver in a clockwise direction as seen from the top A lug on the wind driver comes against a lug on the driver stop plate Fig 128 in the rest position The return spring now has around 3 1 2 turns of initial tension Notice that the end of the return spring hooks to a downward projecting poston the driver stop plate Fig 128 You must remove the driver stop plate to take out the wind driver But removing the driver stop plate allows the return spring to unwind There s no problem in rewinding the return spring on reassembly However you can save time if you prevent th
35. removing the speed knob However for reference set the speed knob to bulb It doesn t matter what film speed setting you use you ll see why in a moment Still with an unfamiliar camera it s good practice to use the fastest film speed setting If you re not familiar with the camera or if you don t have specific service information you might not know whether the camera uses mechanical or electrical coupling Here s one precaution you should note before removing the speed knob calibration plate With many speed knob designs removing the speed knob calibration plate uncovers a compression spring Cameras which use the same speed knob for both the film speed and the shutter speed settings normally have the compression spring You can feel the action of the compression spring as you lift the speed knob to set the film speed Lifting the speed knob BAYONET RETAINING SPRIN WIND DRIVER Figure 21 The three raised lugs of the bayonet retaining spring go up CUTOUT IN DUST SEAL WIND DRIVER ay Figure 22 REMOVE THIS SCREW RIGHT HAND THREAD Figure 23 COMPRESSION RING compresses the compression spring The compression spring then tries to push down the speed knob Hold down the speed knob calibration plate as you remove the center screw Fig 23 Then allow the compression spring to push up the speed knob calibration plate Lilt out the speed knob calibration plate and the film sp
36. rollers you must take out the pinion shafts Two pin screws Fig 171 hold the opening curtain pinion shaft one pin screw passes through each of the two tape ends of the opening curtain winding roller Fig 171 Remove the two pin screws shown in Fig 171 Notice the spacer above the upper tape end Fig 171 this spacer will be loose once you remove the pinion shaft Slide out the pinion shaft toward the top of the camera allowing the two tape ends and the spacer to slip off the bottom of the shaft Next remove the single pin screw at the bottom of the closing curtain winding roller Fig 171 However you ll find that you still can t pull out the closing curtain pinion shaft an E ring clips to a groove in the top of the pinion shaft Fig 171 Take out the E ring shown in Fig 171 Careful there s another spacer right above the E ring Now pull out the closing curtain pinion shaft toward the top of the camera The spacer and the upper teflon guide roller Fig 171 will both be loose You can then remove both curtain assemblies from the camera Fig 172 shows the separate curtains with their associated parts Notice the difference between the two sets of teflon guide rollers the guide rollers which go at the winding lt 4 OPENING CURTAIN PINION SHAFT d SPACER CLOSING CURTAIN SPACER LOOSE SPACER WINDING ROLLER PINION rollers side of the camera are smaller in diameter than are the guide rollers whic
37. shutter should release Looking at the side of the mirror cage you can locate the part which normally actuates the opening curtain latch the opening curtain striker Fig 98 As the mirror reaches the tak ing position the opening curtain striker swings toward the back of the mirror cage The opening curtain striker then comes against the opening curtain latch Fig 90 to free the opening curtain Let s now check the operation of the mirror cage Notice the lug on the mirror lifting lever Fig 98 The mirror latch should now be engaged with this lug If the mirror latch isn t engaged with the lug try pushing the mirror tensioning lever MIRROR TENSIONING LEVER The spring that returns the mirror the mirror return spring is inside the mirror cage The rod upon which the mirror pivots passes through the center of the mirror return spring toward the back of the mirror cage the mirror latch should then drop into engagement with the lug Normally the tensioning lever spring Fig 88 would push back the mirror tensioning lever and allow the mirror latch to engage Next push the mirror tensioning lever toward the front of the mirror cage Fig 99 You re now simulating the action of the mirror cocking lever Fig 88 Pushing the mirror tensioning lever toward the front of the mirror cage tensions the mirror lifting spring Fig 99 One end of the mirror lifting spring hooks to the mirror tensioning lever the
38. side of the latching lug of the closing curtain wind gear Remember the pin on the opening curtain wind gear must turn the closing curtain wind gear during the cocking cycle LUBRICATION Notice the two bearing surfaces on the shaft of the opening curtain wind gear Fig 181 Lightly lubricate these two surfaces with shutter oil Start the opening curtain wind gear into position as shown in Fig 182 Make sure that the pin at the bottom of the opening curtain wind gear sits counterclockwise of the lug on the closing curtain wind gear Fig 183 Before fully seating the opening curtain wind gear fit the opening curtain latching cam over the shaft Fig 184 The in sulated stud on the opening curtain latching cam the stud that closes the X sync contacts should be to your left as you re looking at the front of the camera You should now be able to seat the opening curtain wind gear fully What if the opening curtain wind gear won t seat fully In that case the pin on the opening curtain wind gear is probably coming on top of the latching lug of the closing curtain wind gear Just rotate the closing curtain winding roller to partially wind on the closing curtain That moves the latching lug away from the pin When the lug clears the pin the opening curtain wind gear should drop into place Don t as yet replace the screw that holds the opening curtain latching cam You must first check the timing of the opening curtain wind gear Use you
39. stripe after each adjustment When you can no longer see the stripe you know that the opening curtain is bouncing to the edge of the focal plane aperture but the open ing curtain isn t actually bouncing into the aperture to cause an underexposed stripe Now rotate the brake adjustment screw an additional 1 2 turn in a clockwise direction Besides eliminating curtain bounce this procedure assures that you don t have excessive braking action Too much brak ing action could stop the curtains with the closing curtain bar still in the aperture REMOVING THE SHUTTER COCKED INDICATOR AND THE RELEASE PLATE Since the shutter cocked indicator is quite soft it s easily damaged So you may wish to remove the shutter cocked in dicator early in the disassembly Just disconnect the spring from the side of the shutter cocked indicator Fig 124 The spring may stay on the screwhead the screw that supports the spring also holds one corner of the support shaft assembly But as a safeguard against loss you may wish to completely remove the spring Now remove the screw shown in Fig 124 and lift out the shutter cocked indicator Fig 125 shows the spring for the shutter cocked indicator still in place around th screwhead notice in Fig 125 that we ve repositioned the camera we now have the front of the camera facing us in order to more easily reach the parts at the front The hooked end of the spring Fig 125 connects to the side of t
40. that removing and replacing the curtains will be a lot easier with the release shaft out of your way To remove the release shaft you must take off the exten sion arm Fig 158 Remember the extension arm releases the mirror latch on the mirror cage But the extension arm has a sliding adjustment after loosening the two screws Fig 158 you can slide the extension arm up or down The adjustment controls the overtravel of the release shaft After the mirror releases you should be able to push down the release shaft a slight distance further that s the overtravel For example say you move the extension arm closer to the bottom of the camera The mirror then releases sooner during the downward travel of the release shaft As a result the release shaft has more overtravel it can continue moving down for a greater distance after the mirror releases SPRING FOR CLOSING CURTAIN TCH CAM FOLLOWER LA END AEN CLOSING CURTAIN SLIT WIDTH ADJUSTMENT _ a CAM FOI R END kk CLOSING CURTAIN LATCH oo BULB LEVER ASSEMBLY 3 aa eel Figure 157 You can make the overtravel adjustment after replacing the mirror cage Slowly push down the release shaft until the mirror releases You should then be able to push down the release shaft an additional 0 2mm Insufficient overtravel means it takes too much pressure on the release button to release the shutter And if you have too much overtravel The mirror then rel
41. the camera several times while observing the mirror cage coupling Once you remove the mirror cage you ll have to simulate these actions You ll then be able to test the mirror cage before reassembly Remember as you cock the shutter the mirror cocking lever pushes forward the mirror tensioning lever Fig 88 that tensions the mirror lifting spring at the bottom of the mirror cage The mirror catch lever Fig 88 holds the mirror tensioning lever against the tension of the mirror lifting spring Pushing the release shaft releases the mirror Locate the extension arm on the release shaft Fig 89 As the release shaft moves down its extension arm comes against the mirror latch Fig 89 Now the extension arm pushes the mirror latch out of engagement with the mirror lifting lever And the mirror lifting lever driven by the mirror lifting spring raises the mir ror to the taking position The mirror remains in the taking position as long as the mirror catch lever holds the mirror tensioning lever Fig 88 With any focal plane SLR the closing curtain tells the mirror when to return That way the mirror can t move into the focal plane aperture until the closing curtain has completed the exposure As the closing curtain crosses the aperture the mirror return gear rotates Fig 88 Then after the closing curtain ends the exposure the pin on the mirror return gear strikes the mirror catch lever So the mirror return gear drives t
42. the bottom of the wind shaft Fig 199 The post on the lower wind gear should now be pointing to the body casting screw hole as shown in Fig 199 If you ve properly timed the wind shaft gear Fig 198 the lower wind gear should be properly positioned But you won t be able to change the timing once you ve replaced the transport gears Pentax does provide a technique for changing the posi tion of the post Fig 199 without removing the transport gears However the technique requires that you replace a part The mirror cocking plate mounted on top of the lower wind gear includes the post Fig 199 And you can get dif ferent versions of the mirror cocking plate Each version has a slightly different angle for the center hole Fig 200 So by using a different mirror cocking plate you can change the position of the post without disturbing the wind shaft gear Replacing parts though isn t a convenient adjustment So make sure you properly time the wind shaft gear Fig 198 before assembling the transport gears The position of the post Fig 199 should then be within tolerance Figure 200 STEP FACES FRONT OF Sa S iu 25888 Figure 202 Transport latch Now seat the lower transport gear as shown in Fig 201 Notice in Fig 201 that the slot in the lower transport gear is over the end of the transport latch spring Hold the transport pawl Fig 201 away from the lower transport gear against
43. the locking collar you can turn the setscrew Turning the setscrew repositions the closing curtain latch If you turn the setscrew clockwise the closing curtain latch moves closer to the release cam The release cam then strikes the closing curtain latch sooner giving you a faster shutter speed We ll go through the shutter speed adjustment sequence after you ve covered the shutter mechanism SLOW SPEEDS IN THE PENTAX We mentioned that 1 60 second is the fastest full aperture speed the opening curtain completely crosses the aperture before releasing the closing curtain That s also true of all the speeds slower than 1 60 second But another part comes into play the speeds escapement The speeds escapement sits at the bottom of the camera Fig 111 At the speeds of 1 30 second and slower the speeds escapement holds back the closing curtain after the closing curtain has been released by the opening curtain Your shutter speed setting determines how long the speeds escapement holds the closing curtain Two rods the retard rod and the pallet rod Fig 111 connect the speeds escapement to cams under the speed selec tor To check the slow speed operation start with the speed selector at the bulb position Fig 106 Then rotate the speed selector counterclockwise as seen from the top to the first click stop position that s the 1 second setting Now cock the shutter Push down the release shaft and trip the opening
44. the tension of the transport pawl spring You should then be able to fully seat the lower transport gear Here s how you can check to make sure the lower transport gear is at its correct starting position While watching the transport pawl Fig 201 rotate the lower transport gear very slightly in a counter clockwise direction you should see the transpert pawl move away from the lower transport gear Then rotate the lower transport gear clockwise until you see the transport pawl drop into engagement When the transport pawl drops into the notch at the bottom of the lower transport gear you know the starting point is correct ee You ll probably have to hold down the lower transport gear as you complete the reassembly otherwise the transport latch spring may push up the lower transport gear The transport pawl may then slip underneath the lower transport gear preventing the parts from seating fully Now replace the transport latch Remember the step on the transport latch faces the front of the camera Fig 202 The most critical timing step comes when you replace the upper transport gear Seat the upper transport gear as shown in Fig 203 Notice that the end of the gear slot is almost but not quite touching the transport latch There should be a 0 2mm space gap between the side of the transport latch and the end of the gear slot Fig 203 It s not necessary to try and measure the space gap But you want the end of the
45. toward the top of the screen even though the needle could still move down Or if the needle won t move up the upper galvanometer coil may be open Similarly if the lower coil is open or if the yellow wire connection is defective the needle won t move down Regardless of the malfunction a defective connection or an open coil your most economical repair is to replace the MICROAMMETER complete galvanometer assembly But you should first chech the galvanometer to make sure it s at fault You can check the galvanometer by running current directly through the in dividual coils Yet you have to be careful when checking the galvanometer you don t want to put too much current through the coils Typically you use an ohmmeter to check a galvanometer coil A conventional ohmmeter though puts out too much current That current could peg the needle caus ing damage Or it could mislead you as to the problem How Consider that the upper galvanometer coil has an open You then check for the continuity of the coil by connect ing your ohmmeter between the red wire connection and the blue wire connection Fig 42 You re now running current directly through the upper coil And even though the coil originally had an open you may find that the needle moves up What s happened is that the current from the ohmmeter has welded the open coil So the galvanometer now works However the repair is only temporary The temporary wel
46. tral shafts Fig 167 Each central shaft has a screwdriver slot Use a screwdriver to hold each central shaft stationary Then use your Multispan wrench a large screwdriver or the special tool described earlier Fig 126 to unscrew each tension setting gear in a clockwise direction Fig 166 Now remove the two screws shown in Fig 166 and lift out the take up rollers support plate Slide the closing curtain take up roller toward the bottom of the camera as you lift it from the camera that way you can disengage the upper end of the central shaft from the upper bearing hole CAUTION Watch for the loose endplay washer on the upper end of the closing curtain take up roller Use the same technique to remove the opening curtain take up roller But you now have two loose parts to watch for the teflon guide roller and the endplay washer Fig 168 Remove the two endplay washers one for each take up roller and the teflon guide roller to prevent accidental loss REMOVING THE WINDING ROLLERS Three screws hold the winding rollers support plate Fig 169 Notice that each screw is different one is a countersunk screw one is a shoulder screw and one doubles as a spring hooking post Remove the three screws noting their proper positions Then lift up the winding rollers support plate to clear the lower ends of the winding rollers CAUTION Be careful that you don t turn over the camera after removing the winding rollers suppor
47. up rollers Remember you put 2 complete turns on the closing curtain and 1 1 2 turns on the opening curtain The travel times should now be pretty close to correct Now check to see if there s a slit all the way across the aperture at 1 1000 second You can even get a fairly good idea as to the accuracy of the exposure if you hold up the camera to a fluorescent lamp At 1 1000 second you should see three stripes of light running vertically across the aperture If you see two light stripes your 1 1000 second is closer to 1 500 second You can also make a visual judgment of the side to side variation the eveness of the exposure across the aperture The light stripes should be uniform in width If the stripe at the closing side appears narrower for example you know that the exposure at the closing side is less than is the exposure at the opening side With practice you can get fairly accurate in visually set ting the side to side uniformity But you still need proper test equipment for real precision as well as for speed and efficiency You can then set the travel times to the factory s specifications But depending on the manufacturer there may be one problem with factory specifications you don t always know exactly how the manufacturer measures the travel time For ex ample one manufacturer may specify an edge to edge travel time that s how long the curtains should take to completely cross the focal plane apert
48. 121 Lift off the brass collar to prevent loss You can now operate the shutter there aren t any more loose parts WIND GEAR OPERATION As you cock the shutter notice that the opening curtain wind gear rotates in a clockwise direction Fig 121 The lug on the opening curtain wind gear then comes against the wind gear stop plate Fig 122 And the opening curtain latch drops into engagement with the opening curtain latching cam During the cocking cycle a downward projecting pin on the opening curtain wind gear engages a lug on the closing curtain wind gear So as the opening curtain wind gear rotates clockwise it carries the closing curtain wind gear in the same direction Both curtains then move simultaneously to the cocked position You can release the shutter by holding down the release shaft Then disengage the opening curtain latch Notice what happens now the shutter hangs open Although the opening curtain crosses the aperture the closing curtain remains held by the closing curtain latch Without the release cam there s nothing to disengage the closing curtain latch So the closing curtain remains in the cocked position To release the closing curtain use your tweezers and push the closing curtain latch away from the closing curtain wind gear Fig 122 Fig 121 and Fig 122 also show the action of the shutter cocked indicator When the opening curtain wind gear rotates to the cocked position its small pin comes again
49. 216 Use one spanner type wrench such as your Multispan to prevent the wind shaft gear from turning Then use a second spanner type wrench to unscrew the lower wind gear The wind shaft comes out as a complete assembly Remove the three screws shown in Fig 216 Then lift out the complete wind shaft assembly toward the top of the camera Watch for the loose compression spring Fig 217 The compression spring provides the slipping action for the take up spool it allows the take up spool to slip as the diameter of the exposed film increases Lift out the compression spring from the top of the camera Now open the camera back and remove the take up spool The take up spool has two sections Fig 218 the bot tom section fits inside the top section Be careful of the loose washers A large brass washer fits over the shaft of the bottom section Fig 218 A steel washer fits within the recess at the up per end of the top section How about the spring type clutch for the wind shaft It s part of the wind shaft assembly you just removed Replace ment parts for wind shaft assembly come as a complete unit So if the spring type clutch is defective you must replace the complete wind shaft assembly But you can disassemble the wind shaft for cleaning and lubricating the parts Test the operation of the spring type clutch by turning the wind shaft while you re holding the wind shaft plate The wind shaft should turn smoothly in one di
50. 5 is part of the photo switch The two lower CdS cells control the needle deflection GALVANOMETER WI rocusinc To remove the galvanometer you ll have to take out the NEEDLE SCREEN pentaprism frame Fig 64 Let s consider now that you know you have a defective galvanometer You then want to replace the galvanometer with a minimum of disassembly and with a minimum of unsoldering The technique we ll describe here gets you to the galvanometer with only minor disassembly later we ll describe the technique for removing the complete exposure meter assembly There are only three wires you ll have to unsolder the blue wire the yellow wire and the red wire which go to the galvanometer All three galvanometer wires connect to the exposure meter circuit board Fig 50 However you ve seen that three yellow wires actually connect to the yellow wire land And two red wires connect to the ground land So to locate which wire goes where it s a little easier if you first pull aside the exposure meter circuit board you ll SCREWS HOLDING PHOTOCELL GAI R uawan CIRCUIT BOARD EXPOSURE METER CdS CELLS want the circuit board pulled aside anyway the exposure meter circuit board must be out of the way before you can remove the pentaprism frame Follow the procedures described earlier to pull aside the exposure meter circuit board page 25 Now locate each of the three wires coming from the galvanometer
51. 56 from the terminal board it s not necessary to unsolder the lead wires connecting the ter minal board to the exposure meter circuit board You can then wait until you ve pulled aside the front standard before you do any unsoldering Peel off the leatherette from both sides of the front stan dard You can now reach the five front standard retaining screws Fig 57 But notice that each of the front standard retaining screws passes through a screw mount bushing Fig 58 The screw mount bushings provide your adjustment points for the flange focal distance and for the parallelism After loosening the front standard screw you can turn the threaded bushings Turning the threaded bushings clockwise increases the flange focal distance turning the threaded bushings counterclockwise decreases the flange focal distance The proper flange focal distance for the Spotmatic is 45 46mm that s the distance measured from the front surface of the lens mounting ring to the film guide rails If the parallelism is correct yet the flange focal distance is incorrect you can turn each of the threaded bushings the same amount Yet you normally don t want to disturb the positions of the threaded bushings So before removing the front standard screws you might take a precaution to avoid losing the ad justed positions either scribe the threaded bushings or use a little lacquer to lock the threaded bushings in place Scribing or locking the the
52. ENSION ADJUSTMENT Figure 16 The K1000 has a stainless steel negative battery terminal to minimize corrosion problems REMOVING THE TOP COVER The procedure for removing the top cover remains prac tically unchanged in the various Spotmatic models Starting with the wind lever loosen the three setscrews which hold the counter cover Fig 17 Then lift off the counter cover REASSEMBLY When you replace the counter cover you must properly align the index Fig 17 with the counter dial calibrations First open the camera back the counter dial then returns to its starting position The index should now align with the large dot on the counter dial Fig 9 But it s pretty tough to precisely cence aes RO align the index with a dot So close the camera back HOLDING COUNTER COVER then cock and release the shutter two times Now seat the counter cover Rotate the counter cover until its in dex aligns with the 0 calibration Fig 18 and tighten the three setscrews Figure 17 oa ALIGN INDEX WITH 0 CALIBRATION __ LEFT HAND SCREW a COUNTER DIAL Figure 18 Figure 19 LEFT HAND RETAINING RING Next locate the center screw holding the counter dial Fig 19 this screw has a left hand thread Remove the screw by turning it in a clockwise direction and lift off the counter dial Notice that a flat surface on the inside of the counter dial hole keys to a flat side on the counter shaft Fig 20 NOTE
53. Fig 44 Earlier we mentioned that you can quickly check for a problem in the photo switch circuit by shorting across the tran sistor Fig 43 You can make a similar shorting test to distinguish between a defective transistor and a defective photo switch CdS cell For example consider that the needle doesn t move Yet when you short across the photo switch transistor the needle deflects properly You now know that there s a problem in the photo switch circuit But which component is at fault the transistor or the photo switch CdS cell Figure 44 You can find out quickly by using your tweezers to short across the photo switch CdS cell between the red wire land and the light blue wire land in Fig 44 If the needle now deflects the problem is most likely an open CdS cell And if the needle still doesn t deflect Then you probably have a defective transistor CHECKING THE GALVANOMETER What else could cause the galvanometer needle to remain centered It s unlikely that both current paths Fig 42 would be open However there may be an open inside the galvanometer Notice in Fig 42 that the red galvanometer wire is com mon to both coils So if the needle won t move in either direc tion the red wire connection inside the galvanometer may be defective Or both coils could be open The dark blue wire connects to the upper galvanometer coil Fig 42 A defective connection here would prevent the needle from moving
54. In early Spotmatic models the counter dial return spring is underneath the counter dial the spring unwinds when you lift off the counter dial In later models such as the K1000 the counter return spring acts internally on the counter shaft the spring remains inside the wind lever shaft assembly You can now see the retaining ring holding the counter housing Fig 20 In early Spotmatic models this retaining ring has a normal right hand thread However the retaining ring has a left hand thread in later models including the K1000 Remove the retaining ring by turning it in a clockwise direc tion Then lift off the counter housing The bayonet retaining spring Fig 21 provides the two Positions for the wind lever the ready position away from the camera body and the storage position against the camera body Remove the three screws holding the bayonet retaining spring Fig 21 Then turn the bayonet retaining spring until its three lugs align with the three slots in the wind driver Fig 21 Finally lift off the bayonet retaining spring and the wind lever A pin on the underside of the wind lever passes through the cutout in the wind driver Fig 22 Notice also the dust seal in Fig 22 If you replace the dust seal upside down the cutout won t n with the slot for the wind lever pin So be sure to replace the dust seal as shown in Fig 22 Since the K1000 uses an electrically cross coupled meter you won t lose any timing by
55. POSITIONING SCREW n aside the brake lever The wind gear stop plate then stops the counterclockwise rotation of the opening curtain wind gear Fig 121 Without the brake lever the opening curtain wind gear would strike the wind gear stop plate at top speed That sud den stop would cause the opening curtain wind gear to recoil turning in a clockwise direction And the opening curtain would bounce it would reenter the focal plane aperture after the exposure Most focal plane shutters provide an adjustment on the amount of braking action In the Pentax a screw the brake adjustment screw Fig 122 limits how far the brake lever can move toward the opening curtain wind gear By turning the brake adjustment screw you can then reposition the brake lever Moving the brake lever closer to the opening curtain wind gear increases the braking action moving the brake lever further from the opening curtain wind gear decreases the braking adon i Let s say for example that you re getting curtain bounce You can then increase the braking action But you don t have to remove the speed selector to reach the brake adjustment Rather you can turn the brake adjustment screw from the back of the camera Fig 123 In Fig 123 you re seeing the other end of the brake adjustment screw the end that screws into the body casting Pentax provides a screwdriver slot in the threaded end of the screw to make the adjustment more convenien
56. R TRANSPORT RELEASE SYSTEM DISASSEMBLY TO REACH THE MIRROR CAGE AND SYNC CONTACTS What are the common mirror cage problems in the SLR Here are the ones you ll encounter most frequently For any of these malfunctions you can suspect a problem with the mirror mechanism or with the parts which couple to the mirror mechanism You then want to reach the mirror cage with a minimum amount of disassembly Simply removing the front standard uncovers most of the mirror cage controls Fig 80 Notice in Fig 80 that we ve left the exposure meter assembly in place However assuming you re going further in the disassembly you might remove the exposure meter assembly as described in the last topic Also notice in Fig 80 that you can now reach the sync contacts So if the camera isn t firing the flash you need only remove the front standard Before covering the operation and removal of the mirror cage then let s go through the opera tion of the sync contacts OPERATION OF THE SYNC CONTACTS As you ll recall the X sync contacts close when the open ing curtain uncovers the focal plane aperture That means the part which closes the X sync contacts must turn with the open ing curtain OPENING CURTAIN LATCHING CAM w Notice that the pin on the contact closing lever is not insulated When the contact closing lever closes the FP sync contacts it completes the circuit through ground RED WIRES FROM A N
57. REPLACING THE SHUTTER CURTAINS Start your curtain reassembly with the opening curtain winding roller Fig 173 even though you removed the closing curtain winding roller last Remember the opening curtain pinion shaft is the one which does not have the E ring groove Working from the top of the camera feed the opening curtain pinion shaft through the teflon bearing the bearing that s closer to the front of the camera You must now assem ble the winding roller parts before you completely seat the pi nion shaft Slip the spacer over the lower end of the pinion shaft Fig 173 Then pass the pinion shaft through the two tape ends of the opening curtain winding roller Make sure that the tapes come straight from the tape ends Fig 173 If there s a twist in one of the tapes the tape end may be upside down Then seat the pinion shaft fully Align the threaded holes in the tape ends with the holes in the pinion shaft Now replace the pin screws that hold the tape ends The closing curtain winding roller must sit to the front of the opening curtain tapes that s the reason for installing the Figure 173 Opening curtain winding roller installed opening curtain winding roller first Slightly rotate the opening curtain pinion shaft until the two tapes loop behind the closing curtain bearing Fig 173 These loops allow you to assemble the closing curtain winding roller to the front of the tapes Now feed the closing curt
58. SPEED ADJUSTMENT COUME RETARD ROD GREE TAIL OF SHUTTER COCKED OPENING v INDICATOR CURTAIN WIND R Figure 121 Shutter released The slow speed cam then positions the slow speed cam follower according to the shutter speed setting In turn the slow speed cam follower positions the slow speed coupler to control the retard rod The slow speed adjustment Fig 114 and Fig 119 changes the relationship between the slow speed cam follower and the slow speed coupler So even though the slow speed cam follower stays in the same position you can move the retard rod to change the depth of engagement Proceeding with the disassembly lift out the release cam Fig 118 Both rods the retard rod and the pallet rod are also loose And each rod has a loose part on its upper end Fig 120 The pallet cam follower sits at the upper end of the pallet rod Fig 118 and Fig 120 Notice that the shoulder of the pallet cam follower goes up toward the top of the camera With the speed selector in place the end of the pallet cam follower rides against the pallet control cam Fig 119 Be careful as you lift out the pallet rod a loose spacer fits over the lower pallet rod pivot Fig 120 The retard rod has just one loose part the compression spring Lift out the retard rod with its compression spring There s one more loose part in the camera the brass col lar which fits over the pin on the opening curtain wind gear Fig
59. a complete path to ground Here then is the sequence You can see the flashcord terminal contacts at the other side of the camera Fig 85 The flashcord terminal in the front standard comes against the lower flashcord terminal contact Notice that the front standard has a hole for the FP flashcord terminal Fig 86 In other Spotmatic models the FP flashcord terminal comes against the upper flashcord terminal contact But the K1000 eliminates the FP sync feature by leaving out the second flashcord terminal COVER FOR DELAYED ACTION MECHANISM ACCESS HOLE CHECKING THE SYNC CONTACTS As you ve seen the FP sync contacts serve as a safety switch for the X sync contacts So if the flash isn t firing either set of contacts could be at fault You can use your ohmmeter to check the sync contacts Check the FP sync contacts first remember the FP sync con tacts must be closed before the X sync contacts can fire the flash Connect your ohmmeter leads between the FP TATCHING CAM U gt y flashcord contact Fig 85 and ground any metal portion of the camera You should read an open circuit Then release the shutter at the bulb setting While you re holding open the shutter on bulb your ohmmeter should in dicate continuity Use the same technique to check the X sync contacts But this time connect your ohmmeter between the X flashcord con tact Fig 85 and ground Again you should read an open un til you release the shutte
60. a transistor two bias resistors and a third CdS cell One of the bias resistors and the transistor mount to the under side of the exposure meter circuit board You can t as yet seg Figure 39 PHOTOCELL CIRCUIT BOARD Figure 41 The 4 7K resistor is in series with the upper galvanometer coil see page 42 the transistor But as we ll cover in the next topic you can reach the transistor s leads for troubleshooting purposes The base bias resistor J507 in Fig 39 is at the top of the exposure meter circuit board Fig 33 You can see the remaining component of the photo switch the photo switch CdS cell at the top of the photocell circuit board Fig 40 Like the other CdS cells the photo switch CdS cell sees the light falling on the focusing screen In Fig 41 we ve pulled aside the photocell circuit board to more clearly show the photo switch CdS cell Two screws behind the pentaprism hold the photocell circuit board For most repairs you can leave the photocell circuit board in place However if the camera has a defective CdS celf you must replace the complete circuit board assembly Current flowing through the photo switch CdS cell also flows through resistor Rh Fig 39 Notice that R1 connects between the base and emitter of the photo switch transistor The voltage drop across R1 then provides the forward bias that decides whether or not the transistor conducts current through the exposure meter circuit
61. aded bushings assumes that the adjustments are correct However it s possible that the ad justments for the parallelism and the flange focal distance have been disturbed by impact damage So as a general rule you should measure the flange focal distance after reassembly There s one other caution you ll find a loose tapered bushing under each of the front standard screws The tapered bushings lock the positions of the threaded bushings Also notice that one of the front standard screws is smaller than are the others Fig 57 Under the smaller screw you ll find a smaller tapered bushing and a smaller threaded bushing Now remove each of the five front standard screws Fig 57 And lift out each of the five tapered bushings Fig 59 Be careful to avoid pulling loose the diaphragm resistor wires as you lift aside the front standard FRONT STANDARD RETAINING Figure THREADED BUSHING esas Figure 59 DIAPHRAGM RESISTOR ASSEMBLY Figure 61 2 BRUSH CONTACT RIDES AGAINST CONTACT SURFACE 3 BRUSH CONTACT RIDES AGAINST RESISTOR ELEMENT DIAPHRAGM METERING RING Figure 62 DIAPHRAGM METERING RING END OF METERING RING SPRING THAT CONNECTS TO DIAPHRAGM METERING CONTACT SURFACE RESISTOR ELEMENT E DIAPHRAGM METERING PLATE At the back of the front standard Fig 60 you can now see the terminal board for the diaphragm resistor wires Notice that you can unsolder eith
62. after the exposure If you hear the whirr you know that the pallet isn t disengaging properly the first gear segment must then push its way against the pallet action while returning to the rest posi tion If you don t hear the whirr of the pallet after the ex posure you know that the pallet disengaging adjustment is correct We ll describe the adjustment technique in the next topic Changing the retard engagement provides your slow speed adjustment The slow speed adjustment is similar to the slit width adjustment a setscrew with a locking collar Fig 114 The setscrew accessible from the back of the camera Fig 114 controls the depth of engagement between the upper retard rod lever and the closing curtain wind gear By turning the setscrew clockwise you get more engagement and as a result a slower speed We ll cover the slow speed adjustments in the section Adjusting the Shutter Speeds ADJUSTING THE PALLET DISENGAGING ACTION Let s say that you hear the tell tale whirr of the pallet after the l second exposure Remember the noise tells you that the pallet isn t being completely disengaged The pallet rod isn t pushing the pallet control lever far enough from left to right Fig 113 You can then adjust the position of the upper pallet rod Figure 114 lever Fig 113 Locate the two setscrews in the pallet rod col lar Fig 115 After loosening these setscrews
63. ain pinion shaft through its teflon bearing Make sure that the closing curtain pinion shaft passes to the front of the upper opening curtain tape As the closing curtain pinion shaft starts through the bearing slip the small spacer and endplay washers if used over the lower end Also slip the upper teflon guide roller over the pinion shaft Push up the guide roller until it s positioned in front of the upper opening curtain tape Next slip the closing curtain winding roller over the lower end of the pinion shaft Push down the pinion shaft until it passes through the closing curtain winding roller When enough of the pinion shaft extends fromthe bottom of the closing curtain winding roller seat the lower teflon guide roller Make sure the lower teflon guide roller sits to the front of the lower opening curtain tape Fig 174 Push down the upper teflon guide roller until you can see GuiDE Te the E ring groove in the pinion shaft Then replace the E ring ROGERS Remember that the E ring goes under the small spacer Now push up the closing curtain winding roller until the upper teflon guide roller is against the E ring Turn the pinion shaft until you can see its pin screw hole through the screw hole in the closing curtain winding roller And replace the pin screw that holds the closing curtain winding roller to the pinion shaft The two winding rollers should now be positioned as shown in Fig 174 Notice again how the opening curtai
64. ain wind gear as the opening curtain moves in the release direction In Fig 105 notice what happens when you depress the release shaft The release plate attached to the upper end of the release shaft pushes down the transport latch The transport latch then disengages from the upper transport gear Now the upper transport gear is free to rotate even though the lower transport gear stays in position We ll go through the disassembly and timing of the transport release system a little later You ll then see more clearly how the transport gears operate For now you might just try operating the camera while watching the transport gears Notice how both gears turn together during the cocking cycle But when you reiease the shutter only the upper transport gear rotates Pentax KAOOO AN ue 55 58 61 62 62 65 65 68 70 nR 14 16 78 80 81 86 86 89 91 92 97 101 103 106 107 109 SPEED CONTROL SYSTEM SLOW SPEEDS IN THE PENTAX ADJUSTING THE PALLET DISENGAGING ACTION REMOVING AND CLEANING THE SPEEDS ESCAPEMENT REMOVING THE SPEED SELECTOR WIND GEAR OPERATION ADJUSTING THE OVERTRAVEL OF THE OPENING CURTAIN WIND GEAR ADJUSTING THE CURTAIN BRAKE REMOVING THE SHUTTER COCKED INDICATOR AND THE RELEASE PLATE REMOVING THE WIND DRIVER REMOVING THE SUPPORT SHAFT ASSEMBLY OPERATING THE SHUTTER WITH THE WIND LEVER PARTS REMOVED REMOVING THE TRANSPORT GEARS MINOR AND MAJOR OVERHAUL CHECKING
65. ake up rollers However if you extend the curtains as shown in Fig 175 you ll notice that the closing curtain sits to the front of the opening curtain That s not what you want The opening cur tain should be in front of the closing curtain To reposition the curtains grasp the closing curtain take up roller with your finger Then pass the entire closing curtain take up roller through the opening curtain tapes Once again extend the two curtains to your right the opening curtain should now be in front of the closing curtain Fig 176 Make sure that the closing curtain tapes are straight it s fairly easy to get the tapes twisted as you re working with the take up rollers Then seat the teflon guide roller over the top of the opening curtain take up roller Make sure that the guide roller sits to the front of the upper closing curtain tape Also seat the spacers on the tops of the two take up rollers Hold the two take up rollers as they would normally be positioned the closing curtain take up roller in front with the closing curtain tapes passing around the guide rollers Fig 177 Then pass the lower ends of the take up rollers through their respective holes at the bottom of the camera s body casting And seat the upper ends of the take up rollers in their respective bearing holes at the top of the camera s body casting When you re sure that the take up rollers are properly positioned replace the take up rollers suppor
66. also face the back of the camera But you ll notice that the screw hole in the closing curtain pinion shaft does not align with the camera body cutout That means you ll have to rotate the closing curtain winding roller until one end of the screw hole does face the back of the camera Reach inside the camera and rotate the closing curtain winding roller a partial turn Fig 193 As you re turning the closing curtain winding roller to wind on the closing curtain watch the pinion shaft Stop turning the closing curtain win ding roller when the screw hole points to the camera body cutout Now hold the closing curtain winding roller in place And seat the winding roller pinion over the closing curtain pinion shaft Remember the pinion teeth go down and the counter sunk end of the screw hole faces the back of the camera The screw hole in the winding roller pinion should now align with the screw hole in the pinion shaft Working through the cutout in the body casting replace the screw to hold the winding roller pinion LUBRICATE BEARI WITH SHUTTER Oll Figure 192 Figure 193 Peq BRAKE LEVER j CATCHES OPENING CURTAIN WIND GEAR Replacing the winding roller pinion You re then ready to replace the mirror return gear Rotate the opening curtain wind gear all the way to the cocked position Next seat the mirror return gear over its support bearing make sure that the pin on top of the mirror return Lon points directly to the
67. an only rotate in one direction the direction that winds on the curtains Yet the upper transport gear must SLOT IN LOWER be able to rotate in both directions Kia TRANSPORT GEAR As you ll recall depressing the release shaft pushes down the transport latch The step in the transport latch then moves below the upper transport gear Now there s nothing to pre vent the upper transport gear from rotating freely in the release clockwise direction So when the mirror releases the opening curtain latch the upper transport gear spins with the opening curtain wind gear Allowing the release shaft to move up also allows the transport latch to move up The transport latch spring Fig 145 pushes up the transport latch The step in the transport latch then aligns with the upper transport gear Fig 145 Now lift out the transport latch Note the shape of the transport latch in Fig 146 On reassembly you must insert the transport latch as shown in the drawing Also lift out the upper transport gear Fig 145 You can then see the slot in the lower transport gear that receives the transport latch Fig 147 Finally lift out the lower transport gear On the underside of the lower transport gear locate the notch that receives the transport pawl The transport pawl remains in the camera Fig 148 Notice that the support post for the lower transport gear has a teflon sleeve Fig 149 Because of the teflon sleeve you don t nee
68. ase action Push down the release shaft to depress the transport latch And disengage the opening curtain latch to free the opening curtain REPLACING THE SPEED SELECTOR ASSEMBLY Now reassemble the counter drive parts and the support shaft assembly as described on page 74 Also replace the main FILE THIS SIDE OF SLOT TO OBTAIN PROPER SPACE GAP RETAINING DISC SCREW WITH TEFLON SLEEVE END OF CLOSING CURTAIN LATCH Figure 206 Shutter cocked wind gear the wind driver and the wind lever The reassembly procedure for the wind driver is on page 71 You re now ready to complete the reassembly at the top of the camera Advance the wind lever to cock the shutter Then replace the shutter cocked indicator Make sure that the tail of the shutter cocked indicator is clockwise of the small pin on the opening curtain wind gear Release the shutter before replacing the spring for the shutter cocked indicator Seat the spring coil over the screwhead Fig 206 Connect the hooked end of the spring to the side of the support shaft plate connect the curved end of the spring to the notch in the side of the shutter cocked indicator Before proceeding check the action of the shutter cocked indicator by cocking and releasing the shutter Make sure that the small pin on the opening curtain wind gear doesn t slip under the tail of the shutter cocked indicator Also check to see that the tail of the shutter cocked indicator clears the
69. b of the speed resistor turning ring passes into a speed knob slot But there s a smaller tab on the other side of the speed resistor turning ring The smaller tab passes into the slot of the contact ring Fig 53 The rest of the speed resistor assembly comes out as a unit Take out the three screws holding the fiber board you ll have to partially advance the wind lever to reach one of the screws Then lift out the speed resistor assembly Watch for a loose washer which sits under the speed resistor Looking at the bottom of the speed resistor you can see the contact ring Fig 54 This is the ring that turns when you rotate the speed knob The yellow wire connects to a brush which rides against the contact ring The actual resistance element is on the back of the fiber circuit board Fig 54 You can just see the black resistor ring under the contact ring A brush on the underside of the contact ring rides against the resistor ring BRUSH THAT RIDES AGAINST RESISTOR RING BRUSH THAT RIDES AGAINST CONTACT RING Figure 54 Bottom of speed resistor Figure 53 SCREWS HOLDING SPEED D RESISTOR ING RING SLOT IN Another brush rides against the contact that s the brush pointed out earlier the one that connects to the yellow wire The pictorial Fig 55 shows how the speed resistor works Notice that the black wire connects to the resistor ring As you rotate the contact ring you re just changing the lengt
70. bearing hole for the pallet rod Fig 194 LUBRICATION Before replacing the screw for the mirror return gear you can lubricate the bearing sur face Place just a drop of shutter oil between the inside bearing surface of the mirror return gear and the sup port bearing The oil will work its way around the bearing surfaces as you operate the camera LUBRICATE BEARING SURFACE Leavi i tic ICATE BEARIN e the shutter in the cocked pos tian to replace the mirror catch lever Locate the groove around the shaft of the SPRING FOR MIRROR CATCH LEVER HOOKS TO THIS SIDE OF GROOVE mirror catch lever the coil of the mirror catch lever spring seats around this groove Seat the spring over the shaft of the mirror catch lever as shown in Fig 195 notice that the hooked end of the spring goes up and connects to the side of the mirror catch lever You can then seat the mirror catch lever and its spring as one assembly As you seat the mirror catch lever over its post hold the straight end of the spring against its tension the straight end must hook to the left hand side of the spring hooking post Fig 196 Fig 197 shows the proper position of the mirror catch lever Since the shutter is cocked the end of the mirror catch lever sits behind the pin of the mirror return gear Check to make sure the spring is properly connected the straight end within the groove of the spring hooking post and the hooked end against the side of the mirror ca
71. bly The curtains must overlap sufficiently to protect the film from light during the cocking cycle But the overlap also affects the exposure on the release cycle especially the fast speeds The greater the overlap the faster the speed you ll get The overlap has a significant effect at 1 1000 second and at 1 500 second However the effect becomes less and less as you set slower speeds It has no effect on the full aperture speeds In the Pentax the curtains should overlap one full bar during the cocking cycle that s typical of focal plane shut ters Try looking at the front of the curtains as you cock the shutter You should be able to see only one bar the opening curtain bar The opening curtain bar sits directly in front of the closing curtain bar It s easier to understand the curtain timing of a double roller focal plane shutter after going through the procedure So we ll cover the timing step by step during reassembly DISASSEMBLY TO REMOVE THE CURTAINS Starting at the bottom of the camera disconnect the spring from the mirror catch lever Fig 153 Then remove the E ring Fig 153 and lift out the mirror catch lever with its spring The straight end of the spring hooks within a slot around the post shown in Fig 153 This post also serves as one of the screws holding the winding rollers support plate You ll also want to remove the mirror return gear Fig 154 Notice that the mirror return gear has a pin on its top
72. ck the curtain overlap Fig 8 Notice that the closing curtain bar completely overlaps covers the opening curtain bar Typically Spotmatics and most other focal plane shutters have a full bar overlap one bar completely covers the other bar The overlap prevents light from reaching the film during the cocking cycle Also try watching the curtains as you operate the camera at different shutter speed settings At the slow speeds second through 1 30 second you can hear the sound of the speeds escapement during the exposure The speeds escape ment holds back the closing curtain for the length of time you ve selected on the speed knob Now set the speed knob to 1 60 second 1 60 second is the fastest full aperture speed Here the two curtains com pletely uncover the focal plane aperture during the exposure But the speeds escapement does not hold back the closing cur tain Instead the closing curtain releases after the opening cur tain has completely uncovered the focal plane aperture At the faster speeds the closing curtain releases while the opening curtain is still moving across the aperture The width of the slit formed between the two curtains then determines the shutter speed The faster the shutter speed setting the smaller the slit width a smaller distance between the two curtains Remember though that you only get a full aperture at the speeds of 1 60 second and slower That means 1 60 second is the fastest speed
73. cket gear screws onto the sprocket advance bushing Both parts are difficult to unscrew they have left hand threads and there are no spanner holes However there s a shortcut technique you can use to quickly replace a sprocket Just remove the mirror cocking lever and the lower wind gear at the bottom of the camera remember the lower wind gear screws onto the wind shaft Then take out the three screws holding the lower mechanism plate Fig 220 Lift the lower mechanism plate away from the camera body Working from inside the film chamber you can now slide the sprocket from the sprocket rod Careful the sprocket rod spring and a bushing at the top of the sprocket will be loose When you replace the sprocket make sure the slotted end goes down A slot in the bottom of the sprocket fits over a small brass collar And the brass collar fits over the end of the screw which passes through the sprocket rod LOWER MECHANISM PLATE SPROCKET TTON ems GEAR STEEL WASHER HERE TOP SECTION BRASS WASHER HERE WIND SHAFT SLOT FOR END PLATE OF CLUTCH SPRING WIND SHAFT Figure 219 This is how you get a replacement wind shaft assembly you can t obtain individual replacement components
74. ckwise direction as seen from the top You re now winding on the opening curtain That should free the clos ing curtain The closing curtain should then fire across the aperture to the released position LUBRICATION Lubricate the inside bearing surface of the closing curtain wind gear with shutter oil Just place a tiny drop of oil between the bearing surfaces Fig 179 The oil will then work its way around the in ner surface of the closing curtain wind gear as you operate the shutter Lubricate the latching lug and the retard drive lug with shutter grease Wipe a very light coat of grease on the latching surface of the latching lug Fig 179 Also lightly grease the sloped side of the retard drive lug as well as the side that comes against the upper retard rod lever Remember the sloped side passes under the upper retard rod lever during the cocking cycle if you ve set the shutter to a retard speed You won t have to make any further changes on the tim ing of the closing curtain wind gear But it s a little tricky to time the opening curtain wind gear That s because you must install the opening curtain latching cam at the same time as you re seating the opening curtain wind gear You can t install the opening curtain latching cam after you ve replaced the opening curtain wind gear there isn t enough room There s one more problem the pin on the underside of the opening curtain wind gear must sit against the
75. closing curtain latch CHECKING CURTAIN TIMING When you know that you re going to disturb the curtain timing there are two general rules you should always apply to focal plane shutters 1 Hold open the shutter on bulb Then place a scribe line inside the body casting to mark the position of the closing curtain bar Fig 152 Your scribe line shows you proper timing for the closing curtain wind gear When the closing curtain latch holds the closing curtain wind gear the lead edge of the closing curtain should be a certain distance away from the focal plane aper ture the distance marked by your scribe line You can adjust this distance by changing the tim ing between the closing curtain wind gear and the closing curtain winding roller 2 Note the curtain overlap during the cocking cy cle The amount of overlap tells you the proper timing for the opening curtain wind gear You can change the overlap by adjusting the timing between the opening curtain wind gear and the opening curtain winding roller On reassembly first time the closing curtain wind gear Time the closing curtain wind gear with the closing curtain winding roller until the closing curtain comes to your scribe line Fig 152 Then time the opening curtain wind gear for the proper overlap during the cocking cycle The distance shown in Fig 152 varies in different focal plane shutters In the Spotmatic the proper distance is 6 3mm that s the distance bet
76. d the mirror catch lever Fig 12 latches the mirror tensioning lever Notice in Fig 12 that the mirror cocking lever has returned to its starting position As the lower wind gear completes its rotation it returns the mirror cocking lever The mirror is now tensioned ready for the exposure When you push the release button the mirror lifting spring drives the mirror to the taking position And the mirror releases the opening curtain to start the exposure After the exposure the mirror returns to the Viewing posi tion What part allows the mirror to return The mirror can t return until the mirror catch lever disengages the mirror tensioning lever So look for the part that disengages the mirror catch lever after the exposure CUT OFF THIS SECTION HEAT TREATED CURRENT STYLE MODIFICATION Notice that the mirror return gear Fig 12 rotates as the closing curtain moves across the aperture The mirror return gear then kicks the mirror catch lever out of engagement with the mirror tensioning lever Now the mirror tensioning lever returns to its starting position And the mirror returns to the viewing position The mirror return gear always rotates with the closing curtain it engages a pinion that connects to the bot tom of the closing curtain winding roller 12 Again we ll cover the operation in more detail a litle later But you should always study the operation as soon its you remove the bottom cover you
77. d will soon fail probably after the customer has been using the camera for a few days Your ohmmeter test has then misled you into thinking that you ve corrected the problem Here s a safe way to test the galvanometer run no more than 3 microamperes of current through each coil Fig 45 shows a test set up you can use with a conventional ohmmeter Here we ve disconnected the red galvanometer wire Fig 46 And we ve hooked the positive ohmmeter lead to the red wire Fig 45 DARK BLUE TO GALVANOMETER CONNECTIONS FOR FIXED RESISTOR YELLOW TO GALVANOMETER Figure 46 Exposure meter circuit board But we ve connected a variable current limiting resistor in series with the other ohmmeter lead With the current limiting resistor set to around 390K and with the ohmmeter set to the R X IK scale you ll get a safe current value Connect a lead to the other end of the current limiting resistor Then touch your test lead to either the blue galvanometer wire or to the yellow galvanometer wire Fig 45 You re now running around 3ya directly through a galvanometer coil If you run current through the upper coil Fig 45 the needle should move up slightly Running current through the lower coil should cause the needle to move down slightly You should also get a reading on the ohmmeter the resistance of the coil around 1 3K plus the resistance of your variable resistor A reading of infinite ohms indicates an open coil or a def
78. d any lubrication on the lower transport gear Norm ally though you should use a grease lubricant on a gear that turns with the wind mechanism How about the upper transport ge r It spins with the opening curtain So you know that you don t want a grease lubricant here A part that moves with the curtains normally takes an oil lubricant However it s generally better to leave the upper transport gear dry don t use any lubricant at all Oiling the upper transport gear can cause problems If dirt mixes with the oil you ll get very erratic opening curtain movement Another danger is that the oil could work its way to the gear teeth that would also cause erratic curtain movement ppp SLOT N SUPPORT In Fig 149 you can also see the slot in the support bear 3 LATCH SPRING ing The slot receives the transport latch When you depress the release shaft the transport latch moves down into the slot Figure 149 Figure 150 Using an artist type brush to apply cleaning solution to the take up rollers bearings However if the shutter isn t fully cocked the transport latch doesn t align with the slot As a result you can t depress the release shaft the solid portion of the support bearing blocks the downward movement of the transport latch MINOR AND MAJOR OVERHAUL For routine cleaning and lubrication this may be as far as you ll have to disassemble the camera You can now in dividually clean two of the most critical pa
79. diaphragm setting ring tab is coupled to the top of the diaphragm metering ring tab that s the situation when you have the lens mounted to the camera Setting a larger aperture then pulls down the tab on the diaphragm metering ring As the diaphragm metering ring turns clockwise it programs a larger resistance into the exposure meter system Each f stop has its own resistance value The resistance setting of the diaphragm resistor now tells the exposure meter system what f stop you ve selected An internal spring tries to turn the diaphragm metering ring in a counterclockwise direction So to check the action use your finger to rotate the diaphragm metering ring clockwise you should be able to feel the resistance of the in ternal spring Then release the diaphragm metering ring the internal spring should return the diaphragm metering ring to the position shown in Fig 6 In Fig 6 you can also see the coupling to the diaphragm control ring With the lens removed the diaphragm control ring spring stops down the diaphragm leaves The diaphragm closes to whatever f stop you ve selected Normally though the tab on the diaphragm control ring Fig 7 sits on top of the diaphragm control lever Fig 6 The diaphragm control lever then holds the diaphragm in the full open position Watch the diaphragm control lever as you cock and release the shutter As the mirror starts moving up the diaphragm control lever moves down The dia
80. e return spring from unwinding There s enough tension on the return spring to hold the wind driver against the lug on the driver stop plate So if you re careful you can remove the wind driver and the driver stop plate as one assembly Just remove the two screws holding the driver stop plate Fig 128 Then lift out both parts together Or to be extra safe you can insert a clip to prevent the return spring from unwinding Locate the small hole in the wind driver Fig 128 this hole allows you to insert a retaining clip which will hold the return spring In Fig 129 we ve inserted the retaining clip One end of the clip passes into the wind driver hole the other end passes into the loop at the end of the return spring Your retaining clip doesn t have to be especially strong you can even use a chunk of a paper clip Now remove the two screws Fig 129 and lift out the wind driver and the driver stop plate as one assembly Fig 130 If you ever have to replace a wind driver the return spring comes already tensioned Fig 131 Notice that Pentax installs the spring retaining clip from the underside of the wind driver Just hook the spring loop to the driver stop plate lug Then remove the spring retaining clip to replace the assembly Also notice the two spring loaded pawls on the underside of the wind driver Fig 131 These pawls engage the ratchet teeth of the main wind gear Fig 132 As the wind driver rotates in a counte
81. e linearity resistors Fig 69 your stopped down reading won t be accurate REMOVING THE EXPOSURE METER ASSEMBLY AS A UNIT We ve described procedures for removing the individual components of the exposure meter system However you ll often want to remove the entire exposure meter assembly as a unit just to get it out of your way For example there may be no problem with the exposure meter But you want to get the assembly out of the way to repair the transport shutter or mirror systems Again it s not necessary to remove the pentaprism But if the focusing screen needs cleaning you ll have to remove the pentaprism anyway Remember to loosen just one of the pentaprism adjustment screws Now unsolder three wires Fig 75 from the exposure meter circuit board 2 the diaphragm resistor yellow wire 3 the battery compartment black wire If you wish you can wait and unsolder the diaphragm resistor wires from the front standard terminal board as previously described But there s one more wire you ll have to unsolder unsolder the gray wire from the hot shoe terminal Fig 76 You can now get the exposure meter assembly out of your way Remove the two screws holding the exposure meter cir cuit board Fig 48 Then lift aside the exposure meter circuit board while leaving its wires connected Also remove the speed resistor Just leave the speed resistor wires connected to the exposure meter circuit board Ni i
82. e ll cover the mirror operation in detail a little later For now just cock and release the shutter a few times while observing the parts Notice that the lower wind gear Fig 11 rotates as you cock the shutter A teflon bushing on the lower wind gear passes through a slot in the mirror cocking lever So as the lower wind gear rotates it drives the mirror cocking lever in a counterclockwise direction The right hand end of the mirror cocking lever Fig 11 now comes against the mirror tensioning lever As a result the mirror cocking lever pushes the mirror tensioning lever toward the front of the camera The mirror tensioning lever is part of the mirror cage a clearance slot in the bottom of the camera allows the mirror tensioning lever to engage the mirror cocking lever As the mirror tensioning lever moves toward the front of the camera it tensions the mirror lifting spring You can t as SHUTTER COCKED COUNTER DIAL INDICATOR _ INDEX SLOTTED END OF MIRROR COCKING LEVER MIRROR TENSIONING LEVER MIRROR TENSIONING LEVER TENSIONIN SPRING WINDING ROLLER MIRROR RETURN PINION GEAR Figure 12 Shutter cocked LATCHING SURFACE gt u o MIRROR CATCH LEVER Figure 14 LATCHING SURFACE sZ SGArAce yet see the mirror lifting spring it s the spring at the bottom of the mirror cage which drives the mirror to the taking position Finally with the shutter fully cocke
83. e timing with a few more parts in place Rotate the opening curtain wind gear in a clockwise direc tion until it s latched by the opening curtain latch Then replace the two piece reduction gear and reassemble the wind gear stop plate Be careful when you re positioning the lubrication tube only the end of the material should extend beyond the wind gear stop plate Fig 187 Now hold the wind gear stop plate against the stop plate positioning screw And tighten the two screws holding the wind gear stop plate Finally tuck the lubrication tube around the long headed screw as shown in Fig 188 Once you ve assembled the wind gear stop plate push in the opening curtain latch to free the opening curtain The closing curtain should cross the aperture at the same time Why Because you haven t as yet replaced the closing curtain latch Replace the closing curtain latch and the bulb lever as one assembly Then again turn the opening curtain wind gear to the cocked position When you disengage the opening curtain latch the closing curtain should remain held Check once more to see if the closing curtain aligns with its scribe mark If it does release the closing curtain by pushing the closing curtain latch out of engagement You can now apply a touch of red lacquer to the screw holding the opening curtain latching cam You ll notice that we haven t replaced the parts in the ex act reverse order of disassembly Rather we replac
84. eases too soon and the camera has a hair trig ger A very light touch on the release button releases the shutter Take out the two screws and lift off the extension arm Then remove the E ring and the washer at the bottom of the release shaft Fig 159 Watch for two loose parts as you lift out the release shaft toward the top of the camera the com pression spring and the brass shoulder spacer Fig 158 will be loose REASSEMBLY Start the release shaft into its mechanism plate hole from the top of the camera Then before seating the lower end of the release shaft slip the compression spring onto the release shaft Fig 158 Replace the shoulder spacer with its smaller diameter passing into the camera body hole Finally seat the lower end of the release shaft and replace the i washer and E ring Fig 159 Figure 158 EXTENSION ARM Now remove the two screws holding the X sync contacts Lift aside the X sync contacts as shown in Fig 160 you don t I OPENDIGCURTAI peas pened aerate have to unsolder the wires i 3 CAM LATCHING CAM A screw holds the opening curtain latching cam to the 2 shaft of the opening curtain wind gear Fig 160 Notice that red lacquer locks the screw In this case the red lacquer doesn t secure an adjustment it just prevents the screw from working loose You must remove the screw Fig 160 to take out the curtain wind gears However it s also necessary to remove the wind
85. ective connection CHECKING THE SPEED RESISTOR A defective speed resistor could cause the needle to peg to the bottom of the screen Or you may find there s no change in the needle position as you change the shutter speed and film speed even though the needle works properly when you change the light level and diaphragm setting If the needle doesn t move when you change shutter speeds first check the speed resistor Unsolder the yellow wire Fig 46 from the exposure meter circuit board Then measure the resistance between the yellow wire and the black wire Fig 46 The resistance should increase as you set slower shutter speeds or faster film speeds For example with the film speed set to ASA 100 you should measure around 1K at 1 1000 second you should measure around 50K at the 1 second setting Suppose then that the speed resistor checks out properly Yet you still note the same problem the needle position doesn t change as you rotate the speed resistor What else could cause the malfunction Referring to the schematic Fig 42 you can locate another possible cause Perhaps there s a problem with the fixed resistor which connects in series with the speed resistor If the fixed resistor is open the effect is the same as an open speed resistor Fig 46 points out the fixed resistor lands on the exposure meter circuit board the fixed resistor connects to the underside of the board It s possible that the only p
86. ed the parts in the most convenient sequence for checking the curtain tim ing From here you can reverse your order of disassembly Replace the light trap plate Then cock the shutter by turning the opening curtain wind gear and replace the X sync contact assembly Also reassemble the release shaft Now seat the brake lever in position remember the washer that goes under the brake lever Replace the brake lever screw and connect the brake spring Remember the lug on the opening curtain wind gear strikes the brake lever during the counterclockwise release rotation Fig 190 The spring loaded brake lever then applies a cushioning action to the opening curtain As the opening curtain wind gear completes its rotation it pushes aside the brake lever Fig 191 The wind gear stop plate now arrests the counterclockwise rotation of the opening curtain wind gear Fig 191 REPLACING THE MIRROR RETURN GEAR AND THE WINDING ROLLER PINION Replace the winding roller pinion with the shutter in the released position Take a close look at the screw hole in the winding roller pinion Notice that one end of the screw hole is countersunk the countersunk end receives the screwhead So when you replace the winding roller pinion you ll want the countersunk end of the screwhead facing the back of the camera You ll then be able to reach the screwhead through the camera body cutout Fig 192 The screw hole in the closing curtain pinion shaft must
87. edle up for larger f stops and down for smaller f stops But where s the on off switch for the exposure meter That s one of the unique features of the K1000 there appears to be no on off switch Yet the camera uses a CdS metering system which requires battery power Since the meter constant ly draws current it would seem you could expect very short battery life Ay VA Pentax K1000 OVEREXPOSURE DIAPHRAGM SETTING RING UNDEREXPOSURE SHOT ACCESSORY FILM SPEED WINDOW Figure 2 Figure 3 EYELENS REWIND BUTTON TRIPOD SOCKET Figure 4 The K1000 uses one 1 5V silver oxide battery Eveready S 76 or equivalent ED DOT ON AYONET OUNTING ING 10 tin ru 22 16 84 Actually there is an on off switch The on off switch works automatically according to the amount of light coming through the lens When the light drops very low in intensity a photo switch turns off the meter The needle then centers in the finder mask Fig 2 But the light must drop below EV 2 at ASA 100 to shut off the meter that s a very low intensity So unless you take precautions you can indeed expect excessive battery drain What precautions Well when you re not using the camera you should keep the lens cap in place Yet even light coming through the eyelens can turn on the meter Conse quently you should also keep the camera in its carrying case Since you can t expect camera owners to always
88. eed dial Fig 24 Also lift out the compression spring Fig 25 Notice the slot in the speed knob Fig 26 This slot receives the tab on the underside of the film speed dial Fig 26 Because of the compression spring the reassembly of the speed knob parts can be a little tricky The compression spring tries to push up the film speed dial and the speed knob calibra tion plate as you re assembling the parts So before completing the top cover disassembly we ll go through the reassembly for the speed knob But first lift off the speed knob to see the coupling Figure 24 1 TAB ON FILM SPEED DIAL SLOT IN SPEED KNOB Figure 26 Notice the slot on the underside of the speed knob this slot fits over a tab on the speed resistor turning ring Fig 27 Remember changing either the shutter speed or the film speed sets the resistance of the speed resistor That s how the exposure meter system knows the film speed and shutter speed settings You can disassemble and reassemble the speed knob at any film speed setting As long as you properly align the parts there s no timing to worry about Let s now take a look at the reassembly procedure You might want to practice removing and replacing the speed knob a few times to get the feel of the procedure REASSEMBLY Start with the speed selector Fig 27 in the bulb position You can now rotate the speed selector to any shutter speed setting At bulb the speed
89. eeds There are two key speeds to check in the slow speed range 1 30 second the fastest retard speed 1 8 second the fastest speed with the pallet engaged Check the 1 30 second exposure first If the exposure is too fast or too slow make the adjustment on the slow speed coupler Fig 212 Loosen the locking collar Then turn the setscrew clockwise for a slower exposure turn the setscrew counterclockwise for a faster exposure Next check the exposure at 1 8 second If the exposure isn t within tolerance you may have to make another adjust ment on the slow speed coupler Fig 212 Alternate between 1 30 second and 1 8 second adjusting as necessary until both speeds are within tolerance REMOVING THE WIND SHAFT AND TAKE UP SPOOL Many of the repairs in the K1000 as with other cameras don t require a complete disassembly For example you can remove the wind shaft without taking out the mirror cage But you do have to remove the transport gears and the mirror cocking lever When would you have to remove the wind shaft You may have to replace the take up spool Or you may have to clean the spring type clutch for the wind shaft The spring type clutch allows the wind shaft to turn freely in the film advance direction But it tightens on the wind shaft to prevent reverse rotation So if you stop advancing the wind lever part way through the wind stroke the curtains can t return to the re leased position If the s
90. en the camera back Just pull up the back latch shown here DARK BLUE TO GALVANOMETER DARK BLUE TO PHOTOCELL CIRCUIT BOARD LIGHT BLUE TO PHOTO SWITCH CdS CELL YELLOW TO SPEED RESISTOR YELLOW TO GALVANOMETER W TO DIAPHRAGM RESIST YELLOW TO DIAPHRAGM RESISTOR Wapa SPEED RESISTOR BLACK TO w A DIAPHRAGM Grounn i RESISTOR LAND BLACK TO BATTERY COMPARTMENT RED TO GALVANOMETER RED TO PHOTO SWITCH CdS CELL Figure 50 for a defective transistor Then you must unsolder all the wires Fig 50 shows the wire connections to the exposure meter circuit board Do not attempt to replace the two transistor bias resistors J507 and J508 The resistor values vary according to the par ticular transistor If either resistor is defective replace the complete exposure meter circuit board meeps However you can replace the 12K resistors the one in Disc series with the speed resistor or the one in series with the diaphragm resistor Pentax doesn t supply the resistors in dividually as replacement parts But if you replace an exposure meter circuit board you can save the two I2K resistors from the old board REPLACING THE SPEED RESISTOR Let s say that your troubleshooting procedure has pin pointed a problem to the speed resistor the diaphragm resistor or the galvanometer You can remove and replace any one of these units without disturbing the other two To replace the speed resistor first remove the
91. ent spring Fig 48 The long end of the detent spring hooks to a spring hooking screw The short end passes through a slot in the rewind shaft housing The short end of the detent spring rides against the side of the rewind shaft When you pull up the rewind shaft the de tent spring drops into a rewind shaft slot the detent spring then holds the rewind shaft in the raised position The detent spring drops into another rewind shaft slot when you push down the rewind shaft Removing the detent spring allows the rewind shaft to drop out toward the bottom of the camera Disconnect the long end of the detent spring from the spring hooking screw Fig 48 Then lift out the detent spring and remove the rewind shaft Next unscrew the top cover support post which holds one end of the exposure meter circuit board Fig 48 Also remove the ground screw and washer shown in the same illustration The washer comes against the ground land on the exposure meter circuit board to assure a good ground connection You can now lift aside the exposure meter circuit board Fig 49 In Fig 49 you can see the transistor the second bias resistor and the two fixed resistors mentioned earlier What if you have to replace the exposure meter circuit board perhaps SPRING HOOKING SCREW REWIND SHAFT DETENT SPRING 4 IN SERIES WITH DIAPHRAGM RESISTOR IN SERIES WITH SPEED RESISTOR Figure 49 With the rewind shaft removed you can still op
92. er at the faster speeds Errors introduced by different shutter speed settings aren t all that significant You can really measure the curtain travel time at any shutter speed setting depending on the test equipment With some instruments it s most convenient to use PASS RETARD ROD THROUGH HOLE IN SLOW SPEED COUPLER af Figure 208 Seating the speed selector assembly the bulb setting With other instruments you can use the fastest shutter speed setting Pentax recommends setting the travel time at the fastest shutter speed setting 1 1000 second However you ll sometimes find that you aren t getting a slit at the fastest speed The closing curtain may be releasing too soon or travel ing too fast it then catches up with the opening curtain Try opening the camera back Then hold up the camera to a light source as you re looking through the back of the focal plane aperture Cock and release the shutter at the 1 1000 second setting You should see a flash of light all the way across the aper ture If you see a slit at the opening side but not at the closing side you know that the closing curtain is catching up with the opening curtain Before going to the test equipment then make sure you re getting a slit all the way across the aperture Start by set ting the initial tensions to approximately the normal amounts You should have the proper initial tension on the take
93. er doesn t have a complete cir cuit You can check the continuity of the black wire by using an ohmmeter Remove the battery Then check for continuity between the black wire land Fig 43 and the negative battery terminal Retouching the solder connections at both ends of the black wire often corrects an apparent open You can reach one end of the black wire at the exposure meter circuit board Fig 43 But you ll have to take out the three screws and lift aside the battery compartment to reach the other end NOTE The current Spotmatic models have stainless steel battery terminals It s dif ficult to solder a wire to a stainless steel contact But you can use a conductive adhesive such as conductive epoxy 3 eke Sy Also check for corrosion on the negative battery terminal in the battery compartment Current Spotmatic models have stainless steel battery terminals Consequently corrosion isn t that much of a problem you can clean off corrosion by using a contact cleaner However if you re working on an older camera you may find that the corrosion has damaged the negative battery contact In that case you should replace the complete battery compartment Since the replacement part has the stainless steel contact your customer isn t as likely to en counter another problem with corrosion Now let s say that you are getting the battery voltage to the exposure meter circuit board Where do you check next Try measuring the
94. er the lead wires or the diaphragm resistor wires from the terminal board If you re removing the front standard to reach the shutter mechanism unsolder the lead wires Fig 60 But if you want to replace the diaphragm resistor unsolder the diaphragm resistor wires To remove the diaphragm resistor assembly take out the four screws shown in Fig 60 Notice that the screw in the up per left hand corner and the screw in the lower right hand cor ner have slotted heads these are shoulder screws which posi tion the diaphragm resistor assembly The other two screws have cross point heads Lift aside the diaphragm resistor assembly as shown in Fig 61 Thats as far as you ll have to disassemble the mechanism to replace the diaphragm resistor just unsolder the wires and replace the complete diaphragm resistor assembly However the problem may not require a replacement part If you re getting erratic readings from the diaphragm resistor the assembly may simply require cleaning You can then remove the diaphragm metering ring Fig 61 to clean the brushes and the contact surfaces First discon nect the metering ring spring Fig 61 disconnect the end of the spring that hooks to a hole in the side of the diaphragm metering ring Now rotate the diaphragm metering ring in a clockwise direction The diaphragm metering ring should rotate freely until it comes against a stop Now the tab on the diaphragm metering ring aligns with the scr
95. eter and the diaphragm resistor in the Spotmatic F won t interchange with those in the K1000 But the other parts of the exposure meter are interchangeable BLACK wIRE TO DIAPHRAGM RESISTOR BLACK WIRE TO YELL BATTERY COMPARTMENT prie TO DIAPHRAGM RESISTOR UNSOLDER GRAY WIRE FROM HOT SHOE TERMINAL familiar except for the variable resistor it s the same as the board in the K1000 In fact you can use a Spotmatic F board to replace a K1000 board just remove the variable resistor Fig 74 To adjust the Spotmatic F meter follow the same pro cedures as we ve already described Here you re adjusting the accuracy in the full aperture mode Then push up the stop down switch And use the variable resistor shown in Fig 74 to adjust the accuracy in the stopped down mode The Spotmatic F also illustrates one of the reasons you should avoid disturbing the variable resistors on the photocell circuit board Fig 69 By working back and forth between the two linearity adjustments you ll be able to correct the reading in the full aperture mode But you may then find that the meter reads inaccurately in the stopped down mode You can have the same problem with the K1000 There s a special adapter for the K1000 the K mount adapter which permits the use of screw mount lenses with bayonet mount cameras However when using the adapter you do have to take your reading through a stopped down aperture If you ve disturbed th
96. eturns to the viewing position You can now see why the mirror remains in the taking position for as long as the mirror catch lever Fig 88 holds the mirror tensioning lever Two other actions take place as the mirror rises the FP sync contacts close and the diaphragm stops down to the tak ing aperture You can see the diaphragm control lever under the mirror lifting lever Fig 100 As the mirror rises a downward projecting roller on the mirror lifting lever comes against the left hand end of the diaphragm control lever The right hand end of the diaphragm control lever then moves up allowing the diaphragm to close The mirror lifting lever also closes the FP sync contacts As the mirror rises notice how the lug on the mirror lifting lever comes against the contact closing lever Fig 100 The mirror lifting lever drives the contact closing lever clockwise And the pin on the contact closing lever closes the FP sync contacts You should spend some time simulating the operation Why The operation of the mirror cages in other SLR s is basically the same Also by operating the mirror cage you can locate the latching points Lubricate each of the latching points with a light grease lubricant REMOVING THE MIRROR COCKING LEVER You ve seen that you can remove the mirror cage without taking out the mirror cocking lever So if there s a mirror cage problem you can save a little time by leaving the mirror cocking lever in place H
97. ew hole in the lower right hand corner of the diaphragm metering plate You can then lift out the diaphragm metering ring Fig 62 Notice that the diaphragm metering plate has three cutouts on its inside circumference Fig 62 Also the diaphragm metering ring Fig 62 has three lugs To replace the diaphragm metering ring you must pass its three lugs through the three cutouts that s why you had to rotate the diaphragm metering ring fully clockwise to separate it from the diaphragm metering plate REASSEMBLY To replace the diaphragm metering ring align its tab with the screw hole in the lower right hand corner of the diaphragm metering plate The three lugs should then pass through the clearance cutouts Now rotate the diaphragm metering ring counterclockwise as far as it will go And reconnect the metering ring spring to the hole in the diaphragm metering ring With the diaphragm metering ring removed you can clean the brushes and the contact surfaces Fig 62 The diaphragm metering ring has two brushes one rides against the contact band and one rides against the resistance band Fig 62 Notice in Fig 62 that the yellow wire connects to the resistance band the black wire connects to the contact band So as you turn the diaphragm metering ring you re changing the length of the resistance band between the black wire and the yellow wire Use a commercial contact cleaner or a pure solvent such as Freon to clean the brus
98. gear slot as close as you can get it to the side of the transport latch Yet the parts must not actually touch If you don t have the space gap Fig 203 the transport latch may bind Normally you won t have a problem getting the proper timing But you may run into the situation where the space gap Fig 203 is too large Yet when you move the upper transport gear one tooth you find that the end of the gear slot touches the transport latch You can then make a minor modification to the upper transport gear Use the gear position at which the end of the gear slot touches the side of the transport latch To get the 0 2mm clearance slightly file the end of the gear slot Fig 204 Once you ve timed the upper transport gear replace the retaining disc and the screw Fig 205 The screw has a shoulder which fits through the retaining disc hole Make sure the shoulder passes through the hole as you replace the screw If you aren t careful here the screw may bind the retaining disc The screw will then work loose as you operate the camera You can now check the timing of the transport gears Release the opening curtain by first pushing down the transport latch and then disengaging the opening curtain latch Release the closing curtain by pushing the closing curtain latch out of engagement with the closing curtain wind gear Next rotate the wind shaft gear in a clockwise direction to cock the shutter As the transport gears near the cocked
99. gear stop plate So before taking out the screw holding the opening curtain latching cam we ll go through the pro cedure for removing the wind gear stop plate Fig 161 Before removing the wind gear stop plate you should let off the curtain tensions Otherwise the curtains may pull the winding rollers too far in the release direction that could pull loose the cemented curtains Loosen the setscrews which lock the tension setting worms Fig 162 These setscrews should be sealed with red lac quer Next use a screwdriver to turn the tension setting worms in a counterclockwise direction That lets off the initial tensions In an unfamiliar camera it helps to count the turns of in itial tension on each curtain You then have a starting point for setting up your curtain travel times In the Spotmatic you nn should have two full turns on the closing curtain take up roller RETAINER and 1 1 2 turns on the opening curtain take up roller a How do you know when you ve let off all the tensions Try using your thumb to rotate the take up rollers in a counterclockwise direction you can then feel the spring ten sion on each roller When you can no longer feel any spring ac tion you know that you ve let off all the initial tension It s now safe to disassemble the wind gear stop plate Notice how the lubrication tube passes through a hole in the tube retainer Fig 161 This end of the tube sits within a groove in the top of the wind gear st
100. gh for the solder to flow Avoid holding the soldering iron on the leads too long Here s one place you want to get on and off the solder joint quickly PRLS Ger A poor solder joint is more common than is a defective component That s fortunate the components mounted to the exposure meter circuit board come as a complete assembly So if you find an open transistor you replace the exposure meter circuit board Similarly if the photo switch CdS cell is open you replace the complete photocell circuit board But replacing circuit boards isn t a common repair So we ll wait a moment to describe the procedure Consider first that you are getting the proper voltage at the collector lead Fig 43 Yet the needle still doesn t deflect There could be an open between the collector lead and the CdS cells Fig 42 A black wire connects the photocell circuit board Fig 44 to the collector lead Fig 43 The red wire shown in Fig 44 connects to the ground land on the exposure meter circuit board Fig 43 Check the voltage between the red ground wire and the black wire Fig 44 Your voltage reading here should be the same as your measurement at the collector land Fig 43 If you aren t getting the operating voltage at the photocell circuit board look for a disconnected wire or a bad solder con nection Try retouching the solder connections at both ends of the red wire and of the black wire Fig 43 and
101. h go at the take up rollers side For reassembly reference it helps to keep the loose parts with their particular curtains With Pentax cameras you normally don t have to cement curtains or tapes to the rollers unless one pulls loose That s because replacement curtains come already attached both to the winding rollers and to the take up rollers When you order replacement curtains you also get new take up rollers and new winding rollers So as you go through the curtain installation procedure you ll be taking the same steps as you would to in stall new curtains LUBRICATION Now s the easiest time to clean and lubricate the take up rollers Remember the critical points are the bearing surfaces between the take up rollers and the central shafts During the release cycle the central shafts don t move But the take up rollers must spin around the central shafts as ithe curtains cross the aperture Si To clean the take up rollers first push up one of the central shafts You can then clean the section of the central shaft extending above the take up roller Push down the central shaft to clean the lower end Clean the central shaft for the other take up roller in the same manner As you can see it s much easier to clean the take up rollers after removing the curtains from the camera Now use shutter oil to lu Wicate the take up rollers Place just a touch of oil be and the central shafts
102. h of the resistance path between the black wire and the yellow wire Erratic resistance readings or for that matter even an open could be the result of poor brush contact You might Figure 55 then try cleaning the brushes and the resistor ring by using a contact cleaner But if cleaning the speed resistor doesn t solve the problem you ll have to replace the complete speed resistor assembly Fig 54 REMOVING THE DIAPHRAGM RESISTOR AND THE FRONT STANDARD To reach the diaphragm resistor you ll have to remove the front standard There are only two wires to unsolder the black wire and the yellow wire that go to the diaphragm resistor The black wire and the yellow wire at the exposure meter circuit board Fig 56 connect to a terminal board at the back of the front standard Another pair of wires also connected to the terminal board go to the diaphragm resistor YELLOW wIRE Figure 56 Exposure meter circuit board As you can see in Fig 56 you have a choice as to where you disconnect the two wires You can unsolder the two wires from the exposure meter circuit board Fig 56 before remov ing the front standard Or you can pull aside the front standard and unsolder the two wires from the terminal board Let s now consider that you have only one reason for pull ing the front standard you want to replace or repair the diaphragm resistor In that case you only need to unsolder the diaphragm resistor wires Fig
103. he bridge is balanced But later models com pletely changed the circuit The later models like the K1000 obtain the center the needle concept by using a unique galvanometer design The galvanometer has two separate coils wound on the same frame Fig 34 Current flows through both coils If the current flowing through each coil is the same the needle centers that s the condition which indicates proper exposure So with the needle centered as in Fig 35A current 1 equals current 2 But consider what happens when current 1 is greater than current 2 Fig 34 The needle then moves up Fig 35B And when current 2 is greater than current 1 the needle moves down Fig 35C Figure 34 EXPOSURE METER CIRCUIT BOARD CURRENT 1 GRI CURRENT 2 CURRENT 2 GREATER THAN CURRENT 1 Figure 35 GALVANOMETER 1 WIRES TR DIAPHRAGM RESISTOR Figure 37 Fig 36 puts the concept to work Here we ve added a variable resistor in series with each galvanometer coil Let s say there s more current flowing through path 1 What does the needle do Right it moves up To center the needle you can now use the variable resistors You can either increase the resistance in path 1 or decrease the resistance in path 2 What you re doing is balanc ing the two current values until the current through path 1 equals the current through path 2 You re doing the same thing when you set the camera s controls to cen
104. he mirror catch lever out of engagement with the mirror tensioning lever T Ra i a Now the tensioning lever spring Fig 88 drives the mirror tensioning lever to its starting position Fig 90 Notice that the end of the tensioning lever spring passes through a hole in the mirror tensioning lever The other end of the tensioning lever spring hooks to the side of the mirror cocking lever To remove the mirror cage you must first take out the tensioning lever spring First disconnect the hooked end of the tensioning lever spring from the side of the mirror cocking lever Fig 90 Then remove the shoulder screw Fig 90 Lift out the tensioning lever spring and the keyed washer Fig 91 MIRROR CATCH LEVER MIRROR TENSIONING END OF TENSIONING LEVER END OF TENSIONING LEVER SPRING SPRING THAT HOOKS TO THAT PASSES THROUGH HOLE IN MIRROR COCKING LEVER MIRROR TENSIONING LEVER The keyed washer keys to the flat surface on the mirror cocking lever post Fig 92 Next unsolder the white wire from the upper flashcord terminal contact Fig 93 You don t have to remove the two screws at the top of the mirror cage these are positioning screws Fig 94 Just remove the two screws holding the bottom of the mirror cage Fig 95 The screw closer to the rewind end of the camera is a shouldered screw the other screw is a cross point screw Lift the mirror cage until its upper holes clear the two positioning screws Fig 94
105. he support shaft assembly the curved end of the spring connects to the notch in the side of the shutter cocked indicator Another part you can easily get out of your way is the release plate Fig 125 A nut holds the release plate to the release shaft You can use a large thin screwdriver to unscrew the nut Or you can make a special tool out of an old screwdriver such as the one shown in Fig 126 You don t really need the special tool to remove the release plate nut But the tool does have quite a few applica tions especially in making the shutter speed adjustments as we ll later describe Unscrew the nut Fig 125 and lift off the release plate The hole in the end of the release plate passes over the teflon sleeve on the transport gear screw Fig 127 Also notice that the hole which fits over the release shaft has two flat sides the flat sides key to the two flat sides on the release shaft Fig 127 You may be wondering why we removed the shutter cocked indicator before taking out the release plate Wouldn t the disassembly be easier if we reversed the sequence It prob ably would However you ll now find that pushing the release shaft doesn t disengage the transport gears To release the shutter you ll have to use a small tool such as a small screwdriver and depress the transport latch Fig 127 That s a little more difficult and slower than simply depressing the release shaft So it s normal to replace the
106. hes and the contact surfaces If necessary you can reform the brushes bend the brushes away Irom the diaphragm metering ring to provide better con tact with the diaphragm metering plate Then replace the diaphragm metering ring and again check the resistance readings Remember you re looking for a smooth even resistance change as you turn the diaphragm metering ring If the diaphragm resistor now checks properly resolder the wires to the terminal board and replace the front standard REMOVING THE PENTAPRISM FRAME The galvanometer mounts to the frame which holds the pentaprism and the focusing screen You can replace the galvanometer without removing the pentaprism However when you re going this far in disassembly you ll normally want to remove the pentaprism anyway You can then clean the focusing sereen Locate the two pentuprism retaining springs Fig 63 The upper end of each spring hooks to a tab on the pentaprism re tainer the lower end of each spring hooks to a hole in the pentaprism frame To disconnect each spring grasp the spring loop Fig 63 with your tweezers Then pull down the spring toward the pentaprism frame Once you ve disconnected the lower end of the spring you can slip the upper end off the pentaprism retainer tab Repeat the procedure to remove the other pentaprism retaining spring Now lift off the pentaprism retainer and the pentaprism cover Fig 63 But you can t as yet lift out the pentaprism
107. ides against the pallet control cam At 1 15 second the pallet control cam pushes the pallet rod counterclockwise Fig 113 The lower pallet rod lever Fig 112 and Fig 113 then pushes the pallet control lever from left to right And the pallet control lever moves the pallet away from the star wheel We can now identify the speed ranges in the Pentax 1 1000 1 125 slit width 1 60 full aperture no retard 1 30 amp 1 15 retard with no pallet 1 8 1 second retard with pallet engagement The pallet rod has one other job it disengages the pallet after the exposure To check this action try setting the shutter to the I second exposure one click stop counterclockwise from the bulb setting Then while watching the pallet cock and release the shutter At the end of the exposure you should see the pallet disengage from the star wheel The first gear seg ment may then return easily to its rest position Referring to Fig 113 you can visualize how the closing curtain disengages the pallet After the exposure a pin on the closing curtain wind gear strikes the upper pallet rod lever That drives the lower pallet rod lever against the pallet control lever Fig 113 to disengage the pallet You have adjustments both for the pallet disengaging ac tion and for the depth of retard engagement To check the pallet disengaging action release the shutter at the 1 second setting Listen for the whirr of the speeds escapement
108. isengaging action Fig 115 is probably incorrect But here s a general technique you can use to determine which curtain is bouncing Set the camera to the fasten shutter speed Then open the camera back and hold up the camera to a light source Watch the closing side of the focal plane aper ture as you release the shutter If the closing curtain is bouncing you should be able to see a stripe of light running along the closing side of gt the aperture That s the reexposure If the opening curtain is bouncing you should be able to see a dark stripe running along the side of the aperture Ran Again you normally don t have to worry about closing curtain bounce in the Pentax But you may have to adjust the brake lever to correct the opening curtain braking action Let s consider that you re setting the brake adjustment from scratch Here s a technique you can use Working from the back of the camera turn the brake adjustment screw in a counterclockwise direction to decrease the braking action Keep turning the brake adjustment screw until you see the gray stripe at the closing side of the aperture You now have opening curtain bounce s Next turn the brake adjustment screw a small amount in a clockwise direction And again check the braking action You should see a smaller stripe indicating that the bounce has decreased Keep turning the brake adjustment screw clockwise in small amounts Check the width of the
109. lb lever Fig 109 The bulb cam then prevents the bulb lever from swinging into engagement with the closing curtain wind gear Yet the speed control system must still hold back the clos ing curtain to provide a slit What part now holds the closing curtain wind gear It s the closing curtain latch Fig 109 The cam follower end of the closing curtain latch comes against the release cam You can just see the release cam under the bulb cam in Fig 109 As you cock the shutter notice how the release cam rotates clockwise While still watching the release cam release the shutter You should be able to see the release cam spin in a counter clockwise direction as the opening curtain moves across the aperture Notice that the release cam always turns with the opening curtain both in the cocking and releasing directions That s because the release cam couples directly to the opening curtain wind gear Consider now that the opening curtain is moving across the aperture in the release direction And the release cam is spinning counterclockwise The release cam then strikes the closing curtain latch That disengages the closing curtain latch to free the closing curtain As you observe this action you can see how the Pentax accomplishes one of the basic character istics of focal plane shutters The opening curtain releases the closing curtain The shutter speed depends on how far the opening curtain travels before releasing the closing cur
110. matic models using the two coil galvanometer Here the K1000 provides a good representative But when you re troubleshooting an exposure meter it s best to use the schematic for the actual system use Fig 42 for the K1000 rather than the simplified schematics Earlier we mentioned some of the tell tale symptoms that can direct you toward the problem area Here s a breakdown of the symptoms you might encounter t z the needle always remains centered the needle always shoots to the top of the screen the needle always shoots to the bottom of the screen the needle position doesn t change when you set the f stop the needle position doesn t change when you set the shutter speed Figure 42 Let s start by saying that the needle always remains centered regardless of the light conditions What s your first suspect Jt should be the battery Remember to check the bat tery as your first step in troubleshooting any CdS type meter NOTE You removed the battery with the bottom cover So to test and adjust the exposure meter you must replace the bottom cover and the battery Even with a fresh battery though it s possible that the voltage isn t reaching the exposure meter circuit You can then make your first tests using a voltmeter make sure you re get ting the proper voltages to the circuit boards Notice in Fig 42 that the positive side of the battery con nects to ground the camera body A scre
111. n What do you do then if the counter dial advances too far perhaps two film frame calibrations rather than one Or perhaps the counter dial doesn t advance far enough to latch at the next film frame calibration You then have to replace the counter dial ratchet pawl Fig 136 Pentax supplies three variations of the part One type part 0 3419 has an identification notch in the side The second type part 0 3219 has an identification hole And the third type part 0 03319 has no identification markings If you re doing a lot of Spotmatic repairs you may wish to stock one of each type You can then check and adjust the action at the stage of disassembly shown in Fig 136 Use a 1 7mm screw to hold the counter dial ratchet pawl in place Now rotate the main wind shaft gear in a clockwise direction to cock the shutter The counter advance pinion should rotate until the counter dial ratchet pawl drops into the next tooth slot Cock and release the shutter at least ten times to check the operation That way you re testing every position of the counter advance pinion If the counter advance pinion rotates more than one tooth before the counter dial ratchet pawl drops into engagement or if the counter advance pinion doesn t rotate quite far enough for the counter dial ratchet pawl to drop into engagement you may have to replace the counter dial ratchet pawl But replacing the counter dial ratchet pawl can cause a problem it
112. n tapes pass behind the two teflon guide rollers You can now carefully turn the camera until you re looking at the bottom ends of the winding rollers CLosina CURTAIN TO FRONT Seat the large spacer over the opening curtain pinion shaft the shaft closer to the front of the camera And seat the small spacer over the closing curtain pinion shaft Remember to replace all the endplay washers you noted during disassembly NOTE Replacing the endplay washers in the same positions as you noted prior to disassembly should result in the proper endplay for the pinion shafts However if you ve replaced parts you may have to shim the pinion shafts by adding or removing endplay washers There should be 0 15mm endplay in each pin ion shaft Check the endplay after replacing the winding rollers support plate Just use your thumb to move the winding rollers up and down you should be able to feel the slight endplay As you seat the winding rollers support plate make sure the pinion shafts pass through the teflon bearings Then replace the three screws the countersunk screw toward the front of the camera the shoulder screw in the lower left hand corner and the spring hooking post at the right hand side All three screws serve to precisely position the winding rollers sup port plate So don t tighten any of the screws until you have them all in place Then snugly tighten each of the three screws You re now ready to replace the two t
113. n type spring this is the spring that may force the parts to jump out of place Notice in Fig 136 that the spring pushes the counter dial ratchet pawl into engagement with a pinion This pinion the counter advance pinion is on the counter advance gear it s the pinion you observed earlier while looking through the clearance hole Since the counter advance parts may not want to stay in place it s a little difficult to simulate the operation So you might simply visualize the counter action as we describe it Remember the pinion on the counter advance gear Fig 136 engages the counter shaft gear remaining with the support shaft assembly Fig 137 Cocking the shutter rotates the wind shaft gear Fig 136 in a clockwise direction The counter dial actuator on the wind shaft gear Fig 136 then comes against a tooth on the counter advance gear Fig 138 As the wind shaft gear com pletes its cocking rotation the counter dial actuator advances the counter advance gear one tooth x COUNTERSUNK REWS fF SUPPORT SHAFT ASSEMBLY PINION 7 z Y SPRING ENGAGED 2 MOUNTING WITH a FR a COUNTER SHAFT gt COUNTER SHAFT GEAR y GEAR COUNTER DIAL ACTUATOR RATCHET PAWL SPRING COUNTER DIAL RATCHET PAWL Figure 136 sts 03339 Q SHOULDER B SPACER Figure 138 SHOULDER SPACER Figure 141 That one tooth movement amounts to one film frame calibration on the counter dial To
114. nd gear The heavier spring holds the cam follower section of the closing curtain latch against the setscrew which controls the slit width Turning the slit width setscrew moves the cam follower end of the closing curtain latch closer to or further from the release cam Both springs hook to a notch in the latching section of the closing curtain latch Notice the cujout in the back of the body casting Fig 155 This cutout allows you to reach the screw Rotate the closing curtain winding roller winding on the closing curtain until the screwdriver slot faces the back of the camera Then insert your screwdriver through the clearance slot Fig 155 and remove the screw Now lift off the winding roller pinion Proceeding next to the top of the camera disconnect the bulb lever spring from the mechanism plate post Fig 156 Then unscrew and remove the retaining nut also shown in Fig 156 The bulb lever spring stays with the nut The spring for the closing curtain latch hooks to the lower groove in the mechanism plate post Hold the end of the spring away from the post as you lift out the closing curtain latch and the bulb lever The closing curtain latch may separate from the bulb lever once you remove the parts Fig 157 But for disassembly and reassembly consider the two parts as one unit remove them together and replace them together It s not absolutely necessary to remove the release shaft Fig 158 However you ll find
115. o dry the speeds escapement How about lubrication Some technicians prefer dry moly others prefer shutter oil But Pentax recommends using shutter oil to lubricate the speeds escapement Place a tiny drop of shutter oil at each of the pivot points where the pivots pass through their bearings When you replace the speeds escapement make sure that the fork in the first gear segment straddles the pin on the lower retard rod lever Fig 112 Also be certain that the pallet control lever sits against the end of the lower pallet rod lever Fig 112 REMOVING THE SPEED SELECTOR To clean the curtain control parts you ll have to go fur ther in the disassembly you ll have to remove the speed selec tor Although you could probably clean the mechanism without further disassembly you would have trouble reaching the lubrication points Be sure you keep the camera upright as you remove the speed selector there will be some loose parts Take out the two cross point screws shown in Fig 117 notice that the screw closer to the center of the camera is larger in size Then unscrew the support post Fig 117 and lift out the speed selector assembly NOTE It s a little easier to remove and replace the speed selector with the wind lever removed However you don t have to remove the wind lever The release cam is now loose Fig 118 A slot in the release cam fits over a pin on the opening curtain wind gear Since the opening curtain
116. o the exposure meter circuit board Fig 70 illustrates the concept J504 is the calibration resistor Notice that one end of J504 connects to the collector of the photo switch transistor We ve temporarily left the other end disconnected Consider then that the needle isn t moving up far enough when you test the exposure meter Since you re getting an underexposure indication you know that you need more cur rent through the galvanometer coil Just connect point A to point B in Fig 70 That lowers the resistance in the upper path What i vou connect point A to point C More cur rent then flows through the lower galvanometer coil The nee dle moves down further for the same light conditions You can control the actual amount of additional needle movement by changing the value of J504 Fig 70 Suppose BATTERY 1 5 VOLT SILVER OXIDE that you want the needle to move up Yet when you connect point A to point B the needle moves up too far That means you must replace J504 with a resistor having a larger ohmic value Pentax supplies the calibration resistors in ten different values calibration resistor J504 Notice that the resistors are available in 1 10 step in crements So by changing from one resistor value to the next resistor value you can correct the response by 1 10 EV Going from the 110K resistor to the 1 1MQ resistor changes the response by one full stop Let
117. ob If you can properly set the film speed you know that you ve correctly reassembled the speed knob parts Figure 28 Bulb setting a ee TAB ON SPEED RESISTOR TURNING RING SPEED SELECTOR TIMING DIMPLE Remove the speed knob once again to proceed with the disassembly Open the camera back Then wedge the rewind fork and unscrew the rewind knob You can now see the retain TOP COVER ing ring which screws onto the rewind shaft Use your SCREWS Multispan wrench to unscrew the retaining ring Next lift out the loose spacer which sits on top of the rewind shaft Fig 29 Only three screws now hold the top cover two small screws on the rewind side and one larger screw on the wind side Remove the three screws and slide off the top cover But watch for the cable release pin which fits inside the release but ton the cable release pin Fig 30 is now loose and could fall out There s one other loose part the decorator strip Fig 31 A ridge in the bottom of the plastic decorator strip sits over the top edge of the front decorator plate Lift out the plastic decorator strip before proceeding PLASTIC DECORATOR STRIP Figure 30 Inside top cover Figure 31 The hot shoe contact engages a contact in the top cover accessory shoe RELEASE WHAT S NEXT You may be disassembling the camera to correct a shutter problem or to repair the exposure meter But in either case there are two parts you should replace
118. op plate The other end of the tube tucks around the long headed screw holding the wind gear stop plate When you remove the wind gear stop plate you ll have quite a few loose parts the lubrication tube the tube retainer and some washers Take out the cross point screw holding the wind gear stop plate Fig 161 there should be a locking washer under this screw Then remove the long headed screw Fig 161 the long head also serves to hook the brake spring Lift out the lock washer the flat washer and the tube retainer The lubrication tube normally remains with the tube re tainer However it may come loose We ll describe the pro cedure for positioning the lubrication tube during reassembly Now lift out the wind gear stop plate Also lift out the two piece reduction gear Fig 161 As yet you haven t disturbed any timing However you will be disturbing critical timing when you remove the curtain wind gears Although we briefly described the timing earlier we ll go through the pro TWO PIECE LUBRICATION REDUCTION GEAR em TUI cedure step by step on reassembly The timing procedures apply to most double roller focal plane shutters Take out the screw holding the opening curtain latching cam Fig 160 Then lift out the opening curtain wind gear Careful the opening curtain latching cam Fig 160 will come off the opening curtain wind gear shaft You can now see the closing curtain wind gear Fig 163 The
119. ounterclockwise Notice that the retard rod moves away from the speed selector when you go from the 1 second setting to the 1 2 setting Moving the retard rod away from the speed selector decreases the depth of engagement between the closing curtain wind gear and the upper retard rod lever It then takes less time for the closing curtain wind gear to push its way through the speeds escapement And you get a faster shutter speed tl LOWER RETARD ROD LEVER FIRST GEAR SEGMENT Continue turning the speed selector counterclockwise to the faster speed settings You can then see the retard rod move further away from the closing curtain wind gear But you ll soon reach a setting at which the retard rod suddenly moves toward the closing curtain wind gear that s the 1 15 second setting At 1 15 second you again have full engagement between the closing curtain wind gear and the upper retard rod lever However at 1 15 second and 1 30 second the pallet disengages from the star wheel Fig 112 To check the pallet action first cock the shutter Then watch the pallet Fig 112 as you turn the speed selector counterclockwise from the bulb setting When you see the pallet move away from the star wheel you ve reached the 1 15 second shutter speed The pallet rod Fig 111 is the part that disengages the pallet A cam follower at the top of the pallet rod Fig 113 PALLET CAM FOLLOWER LOWER PALLET ROD LEVER Figure 113 r
120. owever you should remove the mirror cocking lever if you re going further in the disassembly Why When you try cocking and releasing the shutter you may find that the mirror cocking lever causes a bind Since you ve removed the shoulder screw the mirror cocking lever can bind against the mirror return gear As a result you can t complete the cocking stroke Having to hold down the mirror cocking lever as you cock the shutter takes extra time time you want to save in making your tests and adjustments You could replace the keyed washer and the shoulder screw to hold down the mirror cocking lever But it s just as easy to remove the mirror cocking lever from the camera especially if you re going fur ther in the disassembly Remove the E ring which clips the slotted end of the mirror cocking lever to the wind gear post Fig 101 Then remove the washer also shown in Fig 101 You still can t lift out the mirror cocking lever it catches against the mirror return gear So partially cock the shutter until the end of the mirror cocking lever clears the mirror return gear Then lift out the mirror cocking lever Also remove the teflon sleeve which fits over the wind gear post Fig 102 the shoulder of the teflon sleeve goes up and passes through the slotted end of the mirror cocking lever It s a little easier to remove the mirror cocking lever if you first take out the mirror catch lever and the mirror return gear Howe
121. phragm control lever now allows the spring loaded diaphragm to close Again the diaphragm closes to the f stop you ve selected on the diaphragm setting ring After the exposure the diaphragm control lever moves up it returns to the position shown in Fig 6 The diaphragm control lever then opens the diaphragm to the largest aperture ALIGNMENT m Figure 6 The lens locking pin drops into a slot in the back of the lens Fig 7 Pushing in the lens latch withdraws the lens locking pin you can then remove the lens SLOT FOR LENS LOCKING PIN r TAB ON DIAPHRAGM CONTROL RING ra ASAHI SE PENTAx REO D0 TAB ON A KE 1000 Fortes PAARUGAGIC ARTERING DIAPHRAGM SETTING RING TAB OPENING cu CURTAIN CURTAIN i NST CURTAIN ND CURTAIN Tasu CLOSING CURTAIN BAR Figure 8 Curtain movement during cocking cycle OTHER FEATURES OF THE K1000 To open the camera back just pull up the rewind knob Try watching the curtains from the back of the focal plane aperture as you cock and release the shutter note the action of the horizontally traveling focal plane shutter The two curtains Fig 8 move from left to right as you cock the shutter When you release the shutter the opening curtain or first curtain starts the exposure by moving from right to left The closing curtain or second curtain com pletes the exposure when it moves from right to left As you cock the shutter che
122. posi tion watch the transport pawl You should see the transport pawl drop into engage ment slightly before the opening curtain latch engages the opening curtain latching cam With a little practice you can watch both the transport pawl and the opening curtain latch Rotate the wind shaft gear very slowly as the shutter nears the cocked position Again the transport pawl should drop into engagement first The opening curtain latch should drop into engagement slightly after the transport pawl engages the lower transport gear Leave the shutter in the cocked position to test the freedom of the transport latch Here s a technique you can use to assure that the transport latch moves freely Use a screwdriver to hold down the transport latch Then use another screwdriver to turn the wind shaft gear fully in a clockwise direction While holding the wind shaft gear fully clockwise let go of the transport latch the transport latch should remain depressed Now stop applying pressure to the wind shaft gear The transport latch should then spring up on its own If the transport latch pops up as soon as you release the wind shaft gear you know that there s no bind What if the transport latch remains depressed You ll then have to disassemble the transport gears and recheck the timing Apparently the space gap Fig 203 isn t sufficient Ifthe transport gears pass these tests replace the release rod plate Then again test the rele
123. pring type clutch is dirty or distorted you ll note a rough wind stroke To remove the wind shaft first take out the screw above the lower wind gear Fig 213 The screw holds the cover disc Lift out the cover disc Fig 213 and the mirror cocking plate Fig 214 In Fig 214 you can see how the mirror cocking plate keys to the wind shaft Remember you can get different versions of the mirror cocking plate if you need to reposition the post The Figure 214 SLOW SPEED ADJUSTMENT keyed hole in the center of the mirror cocking plate Fig 214 is at a different angle in the other versions Also notice the lug on the mirror cocking plate Fig 214 The lug disengages the rewind button latch When you depress the rewind button to rewind the film the rewind button latch drops into engagement with the sprocket shaft The rewind button latch then holds the sprocket shaft in the disengaged position allowing the sprocket to turn freely in either direc tion When you advance the wind lever to load a fresh roll of film the lug shown in Fig 214 disengages the rewind button latch After lifting off the mirror cocking plate note the two spanner holes in the lower wind gear Fig 215 The lower wind gear screws onto the lower end of the wind shaft However to unscrew the lower wind gear you must prevent the wind shaft from rotating You can now see the purpose of the two holes in the wind shaft gear at the top of the camera Fig
124. r While holding open the shutter on bulb you should read continuity If you have to replace the X sync contacts unsolder the red wires from the flashcord terminal contacts Fig 85 not from the X sync contacts Replacement X sync contacts come with the red wires already connected Just remove the two screws shown in Fig 82 and replace the complete X contact assembly MIRROR CAGE COUPLING TO THE OPENING CURTAIN You ve already seen one purpose of the opening curtain latching cam the cam closes the X sync contacts But the opening curtain latching cam also provides the latching surface for the opening curtain Watch the opening curtain latching cam as you slowly cock the shutter At the end of the cocking stroke you can see the opening curtain latch drop into engagement with the opening curtain latching cam Fig 87 It s now up to the mirror to disengage the opening curtain latch from the opening curtain latching cam Remember in a single lens reflex the mirror releases the opening curtain As the mirror reaches the taking position the opening curtain striker Fig 87 comes against the opening curtain latch The opening curtain striker then drives the opening curtain latch out of engagement with the opening curtain latching cam Now the opening curtain can move across the focal plane aperture REMOVING THE MIRROR CAGE Before taking out the mirror cage make sure you thoroughly understand the operation Cock and release
125. r thumb to rotate the opening curtain wind gear in a clockwise direction The opening curtain should then pick up and turn the closing curtain wind gear in the same direction As you continue turn ing the opening curtain wind gear both curtains should move toward the winding rollers side of the aperture During the cocking cycle check the overlap between the two curtains Remember the curtains should overlap by one bar If you ve installed new curtains it s desirable to have slightly more than a full bar overlap That s because the new curtains may stretch slightly Fig 185 shows the ideal overlap Here s a convenient way to precisely check the overlap Rotate the opening curtain wind gear until the cur tains are about half way across the aperture Hold the opening curtain wind gear with one finger Then use your other hand to turn the closing curtain winding roller Rotate the closing curtain winding roller to move the closing curtain away from the opening cur 4 tain Fig 186 Now allow the closing curtain winding roller to turn slowly in the release direction Watch the curtain bars as the closing curtain moves under the opening cur tain By allowing the closing curtain to move slowly you can fairly easily see how much overlap you have If the overlap isn t right you ll have to adjust the timing Change the timing between the opening curtain wind gear and the opening curtain winding roller pinion Adjus
126. ras and pre Spotmatic Pentax SLR s have used the same transport release system throughout the many dif ferent models Pentax Spotmatics use two separate gears to advance the curtains Fig 103 In Fig 103 we ve used the term transport gears However you ll also see the gears referred to as the clutch gears the intermediate gears and the spill gears Intermediate gears and spill gears are both Pen tax terms the terms you ll see if you re looking at a Pentax parts list But transport gears or transport release gears may be more consistent with the names for parts performing similar functions in other camera designs During the wind cycle the wind mechanism rotates the lower transport gear And the lower transport gear turns the upper transport gear Right now the transport latch locks the two transport gears together Fig 104 You ll also see the transport latch referred to as the clutch latch or in Pentax manuals the spill The upper transport gear engages the opening curtain wind gear So as the wind mechanism rotates the lower transport gear the upper transport gear draws the curtains to the cocked position To release the shutter you must first disengage the upper transport gear from the lower transport gear The lower transport gear remains engaged with the wind mechanism But the upper transport gear must be free to rotate with the opening curt
127. ratic curtain movement Use shutter grease to lubricate parts which turn during the wind cycle but don t turn during the release cycle For example lubricate the main wind gear with shutter grease Place a little grease inside the hole and on the bottom surface of the main wind gear Also lightly lubricate the latching sur faces of the closing curtain latch the bulb lever and the opening curtain latch Always make sure though that you ve thoroughly cleaned the surfaces before applying any lubrication Unfortunately there are some lubrication points you still can t reach For example you can t properly lubricate the closing curtain wind gear without removing the opening curtain wind gear If the parts remaining in the camera body need cleaning and lubrication you can perform the most satisfactory repair with a major overhaul completely disassemble the shutter Performing a major overhaul requires the same steps as does replacing the shutter curtains In either case wait until you ve completely disassembled the camera before cleaning and lubricating the bearing surfaces So before covering any more reassembly steps we ll describe the procedures for removing and replacing the curtains You ll then be able to more clearly see the critical cleaning and lubrication points Figure 151 You can use a small jewelers screwdriver to apply shutter oil But don t apply oil to a dirty bearing Figure 152 Shutter held open by
128. rclockwise direction the pawls turn the main wind gear But as the wind driver returns to the ready position the pawls ride freely over the ratchet teeth Notice that the main wind gear engages the upper teeth of the two piece reduction gear Fig 132 The lower teeth of the reduction gear engage the lower transport gear Turning the main wind gear then rotates the two piece reduction gear And the two piece reduction gear turns the transport spill gears to wind on the curtains There s no timing involved with the main wind gear So you can now lift the main wind gear off the support shaft REASSEMBLY Make sure you thoroughly clean the bearing surfaces of the support shaft Fig 132 Also clean the main wind gear and the wind driver Dirt on the bearing surfaces or a lack of lubrication results in a rough wind stroke Use a light grease lubricant to lubricate the bearing surfaces of the support shaft And lubricate the inside surfaces of the bearing holes in the main wind gear and wind driver Now seat the main wind gear over the support shaft Then seat the wind driver stop plate assembly As you re seating the wind driver stop plate assembly position the stop plate holes slightly counterclockwise of the screw holes in the body casting Fig 133 Once you ve seated the assembly rotate the wind driver in a clockwise direction until the screw holes align And replace the two screws which hold the stop plate
129. rec tion However when you try turning the wind shaft in the other direction the spring type clutch should seize the wind shaft If the spring type clutch fails to prevent rotation in one direction you ll probably have to replace the complete wind shaft assembly However if you feel a rough or gritty action the spring type clutch may simply need cleaning and lubrica tion You can then disassemble the wind shaft assembly Remove the large screw that holds the counter dial ac tuator Careful the counter dial actuator has a loose spacer sitting within its center hole slot on the underside of the counter dial actuator fits over a pin on the wind shaft gear The pin limits how far the counter dial actuator can rotate the counter dial actuator can only move in a small arc Now separate the parts of the wind shaft assembly Fig 219 The spring type clutch remains on the upper end of the wind shaft One end of the spring type clutch fits into the slot in the wind shaft plate Fig 219 You can now clean the individual parts especially the spring type clutch and the wind shaft plate Lubricate the spring type clutch with a light grease lubricant On reassembly make sure the end of the spring type clutch passes into the slot in the wind shaft plate REPLACING THE SPROCKET IN THE K1000 Both the rewind button and the sprocket gear Fig 220 are threaded in place the rewind button screws onto the sprocket rod and the spro
130. roblem is poor solder connections Try retouching the two solder connections for the fixed resistor Fig 46 as well as the solder connections for the speed resistor wires If retouching the solder joints doesn t correct the problem check the fixed resistor Just unsolder the black wire coming from the speed resistor Fig 46 Then measure the resistance between the two fixed resistor lands shown in Fig 46 You should measure close to the indicated resistance 12K in Fig 42 If you read an open you must replace the fixed Tesistor or the complete exposure meter circuit board we ll describe the procedure a little later CHECKING THE DIAPHRAGM RESISTOR defective diaphragm resistor results in a similar maitunction This time though you may find that the needle moves as you change the shutter speed But it doesn t move as you change the diaphragm setting Fig 47 shows the positions of the two wires coming from the diaphragm resistor Since you can reach the wires from the top of the camera you can test the diaphragm resistor without removing the front standard one for the resistor Unsolder the black wire Fig 47 from the exposure meter circuit board Then clip one of your ohmmeter leads to the disconnected black wire touch the other ohmmeter lead to the circuit board land containing the three yellow wires With the lens removed you should read a resistance of around 2K Continue watching the ohmmeter as you turn the
131. rts in the mechanism the transport gears Also you can individually clean and lubricate the other parts which you ve removed These parts in clude the speeds escapement the wind driver assembly the main wind gear and the mirror cage x Going this far in the disassembly would be considered a minor overhaul Here you re not cleaning and lubricating the parts remaining in the camera body Rather you re just cleaning and lubricating the parts which you ve removed A minor overhaul may be satisfactory in many situations Consider that you ve checked the curtain travel times prior to disassembly And you ve found that the curtain travel times are accurate You then know that there s no problem in the curtain wind gears or in the curtain rollers Consequently you won t have to clean and lubricate these parts If the bearings for the curtain rollers appear clean however you may wish to apply a drop of shutter oil to each bearing surface What if the bearings are dirty In that case the additional oil won t do any good oil won t stay on a dirty bearing Dirty curtain bearings indicate the need for a major overhaul completely removing the curtain wind gears and the curtains Some technicians do use a flush cleaning technique Flush cleaning involves working the cleaning solution into the bearing surfaces Fig 150 You must then use compressed air to blow out the solution Although you can do a satisfactory
132. rves to warn you that the shutter is in the cocked position A black section of the shutter cocked indicator shows through the top cover window when the shutter is released The operation of the counter dial is also the same in the many Spotmatic models Try opening the camera back the counter dial should snap to the large dot position Fig 9 Then close the camera back and advance the wind lever The counter dial should rotate one film frame calibration each time you cock the shutter Note how many wind lever strokes it takes to reach the first film frame calibration The first wind lever stroke ad vances the counter dial to the small dot position And the second wind lever stroke advances the counter dial to the 0 calibration Fig 10 When you advance the wind lever a third time you re ready to shoot the first picture REMOVING THE BOTTOM COVER Regardless of the malfunction you ll normally want to begin your disassembly by removing the bottom cover Unscrew the battery compartment cover and lift out the bat tery Then take out the three screws holding the bottom cover Notice that the screw by the tripod socket has a smaller head size than do the other two screws Lift off the bottom cover There s only one loose part to watch for the plastic dust seal which sits over the rewind but ton Fig 11 Remove the dust seal to prevent loss The parts now visible at the wind lever side Fig 11 operate the mirror W
133. s now apply the principle to the actual K1000 circuit Unless the camera has been worked on before you probably won t have a calibration resistor on the exposure meter circuit board There s probably just one fixed resistor the transistor bias transistor J507 The pictorials Fig 71 show how to connect the calibra tion resistor If you need more current through the upper coil solder the calibration resistor to the circuit board lands as shown in Fig 71 A Notice that one lead of the resistor con nects to the transistor s collector the other lead connects to the blue wire of the galvanometer CALIBRATION RESISTOR BLUE GALVANOMETER WIRE YELLOW GALVANOMETER WIRE Figure 71A Figure 71B Figure 72 Spotmatic F If you need more current through the lower coil solder the calibration resistor as shown in Fig 71 B One resistor lead still connects to the transistor s collector But the other lead connects to the yellow wire of the galvanometer Changing fixed resistors isn t the most convenient of ad justments Fortunately you normally don t have to calibrate the K1000 meter If the meter reads within 1 2 stop it s within tolerance And in most instances the meter will be well within the 1 2 stop tolerance range But what if someone else has worked on the camera before you got it If another technician has disturbed the variable resistors Fig 69 you may encounter a linearity problem the meter may read an o
134. selector timing dimple Fig 28 points to the wind lever end of the camera Now seat the speed knob over the speed selector make sure the tab on the speed resistor turning ring passes through the speed knob slot Seat the compres sion spring within the speed knob as shown in Fig 25 Next place the film speed dial in position pass the tab of the film speed dial through the speed knob slot Fig 26 You ll now have to hold down the film speed dial to keep the tab within the slot Otherwise the compression sprin push the film speed dial out of position y 3 Here s the tricky part while you re still holding down the film speed dial replace the speed knob calibration plate You can use your treezers to hold down the film speed dial Then slip the speed knob calibration plate into place As you lift your tweezers use the speed knob calibration plate to hold down the film speed dial The hole in the center of the speed knob calibration plate keys to the two flats on the speed selector Fig 28 Once you ve seated the speed knob calibration plate over the speed selector the B calibration should be pointing to the index You can then replace the center screw The tricky part of the whole procedure is getting the speed knob calibration plate seated without allowing the film speed dial to separate from the speed knob After replacing the center screw Fig 23 test the operation just lift and turn the speed kn
135. speed knob A replacement speed resistor comes with no wires So if you Figure 51 know you have to replace the speed resistor leave the wires Notice that the teeth of the index selector disc are connected to the exposure meter circuit board Instead opposite the timing dimple on the speed selector disconnect the two wires from the speed resistor The yellow That s true regardless of the shutter speed 4 7 i wire connects to the brush that engages the contact ring Fig setting So you can replace the index selector disc z 7 5 s at any shutter speed just make sure the teeth are 51 The black wire connects to the end of the resistor ring we ll opposite the timing dimple cover the operation of the speed resistor in a moment Note the position of the index selector disc at the bulb set ting Fig 46 The teeth of the index selector disc face the pentaprism A lug on the underside of the speed knob engages the teeth of the index selector disc according to the film speed setting Remove the two screws holding the index selector disc Fig 51 You ll then notice that the screw holes in the index selector disc are countersunk that allows the screwheads to sit flush with the top surface of the index selector disc On reassembly make sure you seat the index selector disc with the countersunk ends of the screw holes facing up Now lift off the index selector disc Also lift off the speed resistor turning ring Fig 52 Remember the large ta
136. st the tail of the shutter cocked indicator Now the opening curtain wind gear pushes the shutter cocked indicator in a counterclockwise direction Fig 122 And the red section of the shutter cocked indicator shows through the top cover window When you release the shutter the small pin on the opening curtain wind gear moves away from the shutter cocked indicator A spring then returns the shutter cocked in dicator to the position shown in Fig 121 Now the black sec tion of the shutter cocked indicator moves under the top cover window ADJUSTING THE OVERTRAVEL OF THE OPENING CURTAIN WIND GEAR As you cock the shutter the opening curtain wind gear travels slightly further than necessary This slight overtravel assures that the opening curtain latch always drops into engagement even when the shutter gets a little dirty You can check the overtravel by cocking the shutter Hold the wind lever fully advanced the lug on the opening curtain wind gear should then come against the wind gear stop plate Fig 122 Now allow the wind lever to return to its rest posi tion You should see the opening curtain wind gear rotate slightly in the release counterclockwise direction before the opening curtain latch drops into engagement So with the shutter cocked there should be a slight space gap between the lug on the opening curtain wind gear and the side of the wind gear stop plate Fig 122 points out the 0 2mm space gap If the space gap
137. sur face this is the pin which actuates the mirror catch lever The pin tells you that the gear s timing is critical You could scribe the mirror return gear However there s a convenient reference for reassembly With the shutter cocked the pin on the mirror return gear should point directly to the bearing hole for the pallet rod Fig 154 A Take out the screw Fig 154 and lift out the mirror return gear Notice that the mirror return gear sits over a sup port post What type of lubricant would you use on this bear ing surface Remember the mirror return gear spins as the closing curtain moves across the aperture So since the mirror return gear rotates during the release cycle you need shutter oil The winding roller pinion Fig 154 drives the mirror return gear A screw holds the winding roller pinion to the lower end of the closing curtain winding roller pinion shaft MIRROR CATCH LEVER ve WINDING ROLLER PINION Figure 154 SPRING HOOKS TO THIS SIDE BEARING HOLE FOR PALLET ROD REMOVE SCREW HOLDING MIRROR RETURN GEAR WINDING ROLLER PINION Rog DISCONNECT BULB LEVER SPRING Remove and replace the closing curtain latch and the bulb lever as an assembly as shown on the left At the right you can see the two parts separated Notice that there are two springs on the closing curtain latch The spring pointed out here moves the closing curtain latch toward the closing curtain wi
138. t As with most Pentax adjustments there s red lacquer on the end of the screw Fig 123 You can increase the braking action by turning the brake adjustment screw in a clockwise direction Fig 123 But how do you know if you have curtain bounce Many test in struments will provide this information However with prac tice you can spot curtain bounce by watching the curtains dur ing the release cycle Before describing the procedure though we should iden tify the two types of bounce m gamt 1 opening curtain bounce 2 closing curtain bounce With opening curtain bounce the opening curtain bounces back into the aperture That can cause an under exposed stripe running along one edge of the film frame With closing curtain bounce though you get an overexposed stripe When the closing curtain bounces it gives a reexposure to the edge of the film frame You ve seen that the Pentax brake lever acts against the opening curtain wind gear There s no separate brake for the closing curtain Although many focal plane shutters have separate brakes for the two curtains the Pentax only needs one brake That s because the upper pallet rod lever also serves to cushion the closing curtain Remember the closing curtain wind gear strikes the upper pallet rod lever at the end of the release cycle So in the Pentax it s very unusual to have closing curtain bounce If the closing curtain is bouncing the adjustment on the pallet d
139. t plate there are loose spacers on the ends of the pinion shafts Fig 170 There may also be loose end play washers Pentax uses the endplay washers to individually adjust the endplay of the winding rollers So the positions of the washers aren t always the same in different cameras As you remove the endplay washers be very careful to note their positions Lift the spacer from the opening curtain pinion shaft Fig 170 again watch for endplay washers which may or may not be present in your camera Then lift the spacer from the closing curtain pinion shaft Notice that the spacer for the opening curtain pinion shaft is longer than is the spacer for the closing curtain pinion shaft There s one more loose part the teflon guide roller over the closing curtain pinion shaft Fig 171 Lift out the teflon guide roller You can t as yet lift out the upper guide roller or the winding rollers that takes a little more disassembly P CLOSING CURTAIN ROLLER g k wg OPENING CURTAIN TAKE UP ROLLER COUNTERSUNK F spRING HOOKING ATS SCREW POST K SHOULDER SCREW WINDING ROLLERS SUPPORT miia PLATE Figure 169 Figure 171 SPACER ON OPENING CURTAIN PINION SHAFT SPACER ON CLOSING CURTAIN PINION SHAFT E RING UPPER TEFLON GUIDE ROLLER PIN SCREW HOLDING CLOSING CURTAIN WINDING ROLLER LOWER TEFLON GUIDE ROLLER z lt Er FE g zz ss sz Cry Figure 172 To remove the winding
140. t plate Hold the upper end of each central shaft with a screwdriver as you screw on the tension setting worm gears remember the worm gears have left hand threads Then rotate both take up rollers to draw the curtains to the released position at the right hand side of the aperture Again check to make sure the curtains are positioned properly be especially careful to check for twists in the tapes Also make sure that the closing curtain tapes are passing around the back surfaces of the teflon guide rollers APPLYING THE INITIAL TENSIONS Before timing the curtain wind gears you should apply the initial tensions to the take up rollers Later you ll set the initial tensions precisely to adjust the curtain travel times However by putting a certain number of turns on each take up roller you can set the tensions quite closely Rotate the tension setting worm gears in a counter clockwise direction to apply the tensions You can tell how many turns of tension you ve applied by watching the screwdriver slots in the tension setting worm gears Although the amount of initial tension varies according to the camera here s a good starting point sz OPENING CURTAIN TO 2 FRONT OF CLOSING CURTAIN OPENING CURTAIN TAKE UP ROLLER CLOSING CURTAIN TAKE UP ROLLER ePut 2 complete turns othe closing curtain take up roller ePut I 1 2 turns on the eorn take up roller The tricky part of applying the initial
141. t speeds the speeds of 1 1000 second through 1 60 second These are the slit width speeds the speeds determined by the release point of the closing curtain There are two key Speeds to check in the slit width range 171000 second a 01 125 second But you have only one adjustment for the two abs the slit width adjustment Fig 210 Remember the slit width adjust changes the release point of the closing curtain Use the slit width adjustment to bring in the two key speeds in the slit width range First loosen the lo king collar Fig 210 It helps to use a solvent such as MEK on the locking agent Then turn the locking collar about 1 4 turn in a counterclockwise direction The special tool described earlier Fig 126 works well to loosen the locking collar You can now turn the setscrew to reposition the closing curtain latch MA 126 Y eTurn the setscrew clockwisete m and 1 125 second exposui Es After making the adjustment hold the setscrew in posi tion as you tighten the locking collar In most cases you can bring in both speeds using the one adjustment But you will encounter the exceptions For exam ple you may find that bringing in 1 1000 second makes the 1 125 second exposure too fast You may then have to compromise Try to set the 1 1000 second exposure on the slow side of tolerance while putting the 1 125 second exposure on the fast side to tolerance within 10 at 1 125 second However
142. tain At a full aperture speed the opening curtain completely crosses the aperture the release cam then strikes the closing curtain latch But at a slit width speed the opening curtain is still in the aperture when Figure 109 1 second setting Figure 111 SPEEDS ESCAPEMENT the closing curtain releases The two curtains then form a slit which wipes the exposure onto the film How does the opening curtain know when to release the closing curtain You give the camera this information when you set the shutter speed Try watching the release cam as you rotate the speed selector clockwise to the slit width speeds You can then see the movement of the release cam as the speed selector turns The speed selector just positions the release cam according to the shutter speed setting That decides how far the opening curtain must travel before releasing the closing curtain At the 1 1000 second setting for example the opening curtain barely starts to move when the release cam strikes the closing curtain latch Yet at 1 60 second the opening curtain completely crosses the aperture before the closing curtain releases As is typical your slit width adjustment is on the closing curtain latch Locate the setscrew and the locking ring at the front of the closing curtain latch Fig 110 Both parts should be locked in place with red lacquer The slit width adjustment has its greatest effect on the fastest speeds After loosening
143. take these precautions your customers will be coming to you with a relatively simple problem a dead battery Remember with a dead battery the needle remains centered in the mask And the customer may think that the controls are properly set for the light conditions As a result he gets underexposed or overex posed pictures You should then check to see if the needle moves as you change the light conditions and the camera settings If there s no needle movement replace the battery as your first step in troubleshooting The K1000 uses one silver oxide 1 5 volt battery To remove the battery unscrew the battery compartment cover at the bottom of the camera Fig 4 The negative terminal of the battery goes down the positive terminal makes the ground connection After replacing the battery again check the meter s op ra tion Like other Spotmatics the K1000 uses an electrically cross coupled exposure meter Changing the shutter speed set ting the film speed setting or the diaphragm opening pro grams a resistance value into the exposure meter system Set the shutter speed by rotating the speed knob Fig 3 To set the film speed lift and rotate the speed knob The tilm speed setting then shows through a window in the speed knob calibration plate When you re setting the film speed or the shutter speed the speed knob programs the resistance setting of a variable resistor The variable resistor sits under the speed knob However
144. tch lever Then replace the E ring Figure 197 Shutter cocked LUBRICATION Lubricate the latching end of the mirror catch lever with shutter grease this is the sur face that engages the mirror tensioning lever of the mirror cage REPLACING THE TRANSPORT GEARS There are several critical timing points to consider when you replace the transport gears Although you disassembled the transport gears with the shutter released you ll want the shutter cocked for reassembly you ll see why in a moment Rotate the opening curtain wind gear Fig 198 to the cocked position Now is a good time to check the overtravel of the opening curtain wind gear Remember you should _ have a 0 2mm space gap between the lug on the opening curtain wind gear and the side of the wind gear stop plate Fig 1982F necessary adjust the stop plate positioning screw from the back of the camera Before replacing the transport gears time the wind shaft gear Fig 198 You can now turn the wind shaft gear con tinuously in a clockwise direction a slip spring on the wind shaft prevents reverse rotation Turn the wind shaft gear to the position shown in Fig 198 Notice that the counter dial actuator points to the support post Also if you draw an imaginary line through the support post as shown in Fig 198 the line passes across the two holes in the wind shaft gear Why s this timing important It determines the position of the lower wind gear at
145. tension is in find ing the right starting point the point at which there s no in itial tension on the take up rollers But there s a technique you can use to find the starting point a technique you can also ap ply to other focal plane shutters S Let s say you re starting withthe closing curtain take up roller Insert your screwdriver or the special tool Ey described earlier into thes screwdriver slot in the rotate the eave s complete turns After applying the initial tension hold the tension setting worm gear in position as you insert the tension setting worm Temporarily tighten the setscrew to hold the tension setting worm in position But don t as yet apply any locking agent to the setscrew You ll later use the tension setting worm to precisely set the curtain travel time Repeat the procedure to apply the initial tension to the opening curtain take up roller You can then check to make sure the curtains are tracking properly as you install and time the curtain wind gears TIMING THE CURTAIN WIND GEARS Earlier we mentioned the standard technique for timing the curtain wind gears in a double roller focal plane shutter Here again is the procedure 1 Time the closing curtain wind gear to hold the closing curtain the proper distance behind the focal plane shutter at bulb 2 Time the opening curtain wind gear for the proper curtain overlap during the cocking cycle To time the closing curtain wind gear
146. ter the needle The CdS photocells control the resistance in path 1 Fig 36 The shutter speed film speed and diaphragm controls set the resistance in path 2 So as you change the controls you re setting the resistance in path 2 to equal the light controlled resistance in path 1 Fig 37 completes the circuit The two photocells con nected in parallel see the light falling on the focusing screen As the light intensity increases the resistance in path 1 decreases Consequently more current flows through path 1 You must now decrease the resistance in path 2 to center the needle The film speed and shutter speed settings program the resistance of the speed resistor in path 2 the speed resistor you ll recall sits under the speed knob Fig 38 The diaphragm opening programs the resistance of the diaphragm resistor Fig 37 remember the diaphragm resistor sits behind the front standard Setting a smaller aperture decreases the resistance of the diaphragm resistor Also setting a slower film speed or a faster shutter speed decreases the resistance of the speed resistor Consider again that the light level has increased The resistance of the photocells then decreases sending more cur rent through the upper galvanometer coil As a result the needle moves up you get the overexposure indication You must then set either the shutter speed or the diaphragm opening to center the needle Since the light level has increased
147. tes in the direction that draws the curtains to the cocked position opposite to the direction of rotation during the release cycle If the shutter s at a slow speed setting the upper retard rod lever sits in the way of the closing curtain wind gear The retard drive lug on the closing curtain wind gear must then get past the upper retard rod lever Yet the retard drive lug can t simply push aside the upper retard rod lever that would be forcing the retard rod to rotate in the wrong direc tion Instead a sloped surface on the retard drive lug just passes under the upper retard rod lever as the closing curtain wind gear rotates to the cocked position That pushes up the retard rod against the pressure of the compression spring Once the retard drive lug clears the upper retard rod lever the compression spring pushes down the retard rod Now the upper retard rod lever is once again in the path of the retard drive lug You ll be able to see the action more clearly as you disassemble the curtain wind gears For now try cocking the shutter at the l second setting notice how the retard rod moves up during the cocking cycle Then when you reach the cocked position the compression spring Fig 111 pushes down the retard rod The retard rod can also swing in and out toward you or away from you in Fig 111 You can observe this movement by rotating the speed selector Watch the retard rod Fig 111 as you turn the speed selector c
148. times Why can t you just set up the tensions by turning the tension setting worms a certain number of turns If you know the proper number of turns you can set the travel times fairly close However the precise amount of tension for each curtain will vary slightly from camera to camera For example suppose that the manufacturer specifies a curtain travel time of 14 5 milliseconds If the camera is new and the take up rollers springs are in good condition it takes a certain amount of initial tension to reach this travel time But an older camera needs more tension before the curtains will move at the proper speed The curtain travel time may also vary slightly at different shutter speeds At the bulb setting for example nothing restricts the opening curtain The curtain can then travel at top speed But at an instantaneous speed setting the opening cur tain must kick the closing curtain latch out of engagement As a result the opening curtain can t gather full momentum before entering the aperture Changing the release point of the closing curtain by setting different shutter speeds also affects the opening curtain travel time The closing curtain travel time varies at the slow speeds With no retard the closing curtain has a chance to gather momentum before entering the aperture But the speeds escapement holds back the closing curtain at the speeds slower than 1 60 second The travel time of the closing curtain then becomes fast
149. ting the tim ing here can present a problem when you lift the opening curtain wind gear to change its position the opening curtain latching cam may come off the shaft Hold the opening curtain winding roller with one finger Then lift the opening curtain wind gear slightly just enough to disengage the opening curtain winding roller pinion but not enough to allow the opening curtain latching cam to drop off the shaft Then rotate the opening curtain winding roller in one direction or the other to correct the overlap ROTATE OPENING CURTAIN WIND 3 GEAR TO ADVANCE CURTAINS ROTATE CLOSING CURTAIN H WINDING ROLLER TO PROVIDE k SUT CLOSING CURTAIN Figure 186 While checking the overlap you can also check to see that the slit formed between the two curtains is uniform The two curtain bars should be parallel with one another providing a uniform slit Figure 189 Release the shutter by disengaging the opening curtain latch Turning the opening curtain winding roller clockwise as seen from the top decreases the overlap turning the opening curtain winding roller counterclockwise increases the overlap Once you ve adjusted the overlap replace the screw which holds the opening curtain latching cam Now everything s locked in place you won t lose your curtain timing However don t as yet apply any locking agent to the screw that holds the opening curtain latching cam wait until you ve rechecked th
150. to free the jammed mirror tensioning lever You can now push the mirror tensioning lever toward the front of the camera until it s once again latched by the mirror catch lever Fig 15 A simple repair right But if the customer again jars the camera with the shutter cocked he may have the same problem You can make a more permanent repair by modify ing the mirror catch lever Just cut off the top lip indicated in Fig 13 then file the latching surface to match the shape of the current style Don t try to file the heat treated section of the mirror catch lever Fig 13 While you re at the bottom f the camera also examine the battery compartment The black wire connects to the negative battery compartment terminal Fig 16 This wire goes to the exposure meter assembly at the top of the camera The two red wires which are twisted together go to the X syne contacts You can t as yet see the X sync contacts they re inside the camera The other ends of the red wires Fig 16 go to the flashcord contacts Fig 16 also shows the curtain tension setting adjustments You ll use these adjustments to set the curtain travel times how fast the curtains move during their release travel We ll cover the adjustment procedures in the shutter section of this manual MIRROR TENSIONING LEVER ENGAGED BY MIRRI 1OR CATCH LEVER NEGATIVE CLOSING CURTAIN TERMINAL f TENSION ADJUSTMENT t BATTERY OPENING CURTAIN COMPARTMENT T
151. tscrews determine the distance between the focusing screen and the mirror The three setscrews Fig 78 provide your adjustment for the focusing screen height For example say that the focus at the film plane is correct But the image formed on the focusing screen is out of focus at infini ty You can then change the height of the focusing Screen to adjust the focus of the viewed image m 2 e PENTAPRISM At first glance it appears that the focusing screen adjust ment setscrews would be difficult to reach However you don t have to remove the pentaprism frame to reach the setscrews In fact you don t even have to disasssemble the camera just remove the lens You can then reach the other ends of the focusing screen adjustment setscrews Pentax conveniently provides screwdriver slots at both ends of each screw So by using a screwdriver with a long blade you can work through the lens opening to adjust the focusing screen height Turning the three setscrews allows you to correct the focus at the corners as Kona grind so VERTICAL well as at the center of the focusing screen Figure 79 Assembly with pentaprism in place Pentax K 1000 pes RAA a contents DISASSEMBLY TO REACH THE MIRROR CAGE AND SYNC CONTACTS OPERATION OF THE SYNC CONTACTS CHECKING THE SYNC CONTACTS MIRROR CAGE COUPLING TO THE OPENING CURTAIN REMOVING THE MIRROR CAGE OPERATION OF THE MIRROR CAGE REMOVING THE MIRROR COCKING LEVE
152. ure Another manufacturer may specify the travel time measured a certain distance in from each edge of the aperture In Pentax Spotmatic models the edge to edge travel time is 14 milliseconds Also many test instruments won t read an edge to edge travel time A test instrument normally uses two photosensors spaced a certain distance apart The less the distance between the two photosensors the shorter your travel time reading should be It takes less time for the slit to move 34mm for ex ample than it does for the slit to move 36mm The instruction manual for the particular instrument normally gives you the proper travel times for representative cameras Most test instruments though space the photosen sors 34mm or 32mm apart In Pentax Spotmatic models the proper travel time for the curtains to travel the 32mm distance is 12 5 milliseconds Normally you should start with the opening curtain Ist curtain travel time adjustment Adjust the opening curtain tension setting worm Fig 209 for the proper travel time Then adjust the closing curtain tension Fig 209 for the same travel time Some test instruments will display both travel times simultaneously Others require that you make separate tests for the two curtains Next check the side to side variation at the fastest shutter speed Test the exposure at the opening side of the aperture Then test the exposure at the closing side of the aperture The two exposures should
153. ure 107 OPENING CURTAIN Figure 108 RELEASE SHAFT DEPRESSE TAIL OF BULB LEVER PS I ROOVI r SED DROPS INTO Gi IN RELEASE SHAFT 4 MIRROR RETURN GEAR The latching end of the bulb lever then swings into the path of the closing curtain wind gear Right now it s a little difficult to see the curtain wind gears But the drawing Fig 108 shows how the curtain wind gears control the curtains Notice in Fig 108 that the opening curtain wind gear sits above the closing curtain wind gear The closing curtain wind gear engages the pinion of the closing curtain winding roller Stopping the rotation of the closing curtain wind gear then Stops the movement of the closing curtain With the release shaft depressed the bulb lever engages a lug on the closing curtain wind gear The bulb lever then stops the rotation of the closing curtain wind gear before the closing curtain can enter the aperture The shutter remains open as long as the bulb lever engages the lug on the closing curtain wind gear However when the release shaft returns to its rest position it pushes the bulb lever out of engagement with the closing curtain wind gear In Fig 107 you can see the tapered section of the release shaft this section comes against the bulb lever to free the closing curtain Now try setting the speed selector to an instantaneous speed setting As you depress the release shaft notice how the bulb cam blocks the bu
154. ver unless you re going through a complete disassembly you won t have to remove these parts You can often save a lit tle time by leaving the mirror catch lever and the mirror return gear in place TRANSPORT RELEASE SYSTEM As you operate the camera with the mirror cage removed you ll notice that it takes two steps to release the shutter 1 You must hold down the release shaft 2 You must disengage the opening curtain latch sata et Why the two steps Focal plane SLR s have to latch the curtains at two points First the curtains must be latched to the wind mechanism The wind mechanism can then advance the curtains to the cocked position But in order for the curtains to release there must be a way to disengage the curtains from the wind mechanism i Secondly the opening curtain must be latched by the opening curtain latch If it weren t for the opening curtain latch the curtains would release as soon as they were disen gaged from the wind mechanism That s not what you want Remember in an SLR the mirror releases the opening curtain If the opening curtain didn t wait for the mirror the mirror would still be in the aperture during the exposure The design and operation of the opening curtain latch re main pretty consistent in different SLR s But the transport release systems the systems that disengage the curtains from the wind mechanisms vary considerably However Spot matic came
155. verexposure under bright light conditions and an underexposure under dim light conditions or vice versa Changing the calibration resistor J504 won t correct the problem Remember J504 provides a total response adjust ment You may then have to work back and forth between the two variable resistors to correct the linearity Again adjust J209 for a high light level adjust J210 for a low light level Alternately you can replace the complete photocell circuit board A replacement photocell circuit board comes with the variable resistors already adjusted VARIATIONS ON THE K1000 METER We mentioned that several other Spotmatic models have nearly the same exposure meter design The early screw mount Spotmatics combine balanced bridge circuits with stopped down metering But later screw mount models feature full aperture metering using circuits similar to the one you ve studied The screw mount lenses for full aperture metering work the same way as do the bayonet mount lenses a tab on the diaphragm setting ring rotates the camera s metering ring But the earlier screw mount Pentax lenses don t have the tab on the diaphragm setting ring That s because the first lenses were designed for stopped down metering When Spotmatics switched to full aperture metering however they didn t make the older lenses obsolete You can use the older lenses on the full aperture metering cameras But you must take your exposure reading through a stopped
156. voltage between the ground land and the collector of the transistor Fig 43 You should measure very close to the full battery voltage When conducting the tran sistor only drops a fraction of a volt If you measure 0 volt at the collector the transistor isn t conducting There could be a problem in the bias circuit Or the transistor itself could be defective You can make a quick test of the transistor by using your tweezers to short between the emitter and collec tor leads Fig 43 The short bypasses the transistor So if the needle now moves you ve isolated the prob lem to the photo switch circuit Fig 43 also shows the other approximate voltages you should measure in the photo switch circuit Again these voltage measurements assume a fresh battery If you aren t getting the proper voltage readings and if shorting across the transistor turns on the meter you know that the problem is in the photo switch circuit The problem could be an open transistor an open photo switch CdS cell or an open bias resistor A poor solder joint could also cause the problem So you might first try retouching the solder joints on the exposure meter circuit board Retouch the connections for the transistor for the base bias resistor J507 and for resistor J508 Fig 43 CAUTION If you do retouch the transistor leads be careful to avoid overheatingythe transistor The sistor will be damaged by too Touch your soldering iron enou
157. w and washer make the ground connection between the camera body and the exposure meter circuit board Fig 43 The screw holds the ground washer in firm contact with the ground land Since the camera has a positive ground all your voltage measurements will be negative with respect to ground Touch your positive voltmeter probe to the ground land Fig 43 Then touch your negative voltmeter probe to the test points on the circuit boards Check first for the battery voltage A black wire Fig 43 connects the negative battery terminal to the exposure meter circuit board With the battery installed measure the voltage between the ground land and the black wire land Fig 43 You should measure the full battery voltage around 1 57 volts with a new battery 3508 EMITTER CONNECTION 1 57V COLLECTOR 14V BIAS RESISTOR J507 GROUND GROUND WASHER BLACK TO co BLACK TO PHOTOCELL COMPARTMENT BOARD 1 57V 1 54V Figure 43 the K1000 is typical of er makes the connection RA the pressure of the washer i to make a good electrical connection to the camera What else could cause the problem If the battery voltage isn t reaching the exposure meter circuit board the problem could be with the black wire Fig 43 The black wire you ll recall connects the exposure meter circuit board to the negative battery terminal So if one end of the black wire is disconnected or has a poor solder connection the met
158. ween the lead edge of the focal plane aperture and the lead edge of the closing curtain By using the scribing technique however you don t need factory specifica tions You can see why the closing curtain position is important if you ll recall how the camera operates at the slow speed set tings Remember the closing curtain creeps toward the focal plane aperture while the speeds escapement engages the closing curtain wind gear But the closing curtain wind gear pushes its way past the speeds escapement before the closing curtain actually enters the aperture Suppose then that you ve set the distance shown in Fig 152 to less than 6 3mm That means the closing curtain sits too close to the focal plane aperture when the closing curtain latch is engaged As a result the closing curtain creeps into the aper ture during the slow speeds With the speeds escapement installed you can check the action from the back of the aperture Open the camera back Then while looking at the back of the focal plane aperture operate the camera at a slow speed setting If you see the lead edge of the closing curtain start to enter the aperture while the speeds escapement is engaged you know that the closing curtain timing is incorrect How about the opening curtain timing Here you re tim ing the opening curtain wind gear for the proper overlap dur ing the cocking cycle You generally want the same amount of overlap as you noted prior to disassem
159. wind gear couples to the slot the release cam always rotates as the opening curtain moves SLOT IN RELEASE CAM Figure 117 Its possible that the release cam stayed with the speed selector during disassembly The shaft of the release cam fits through the speed selector hole Fig 119 If the release cam in your camera did stay with the speed selector separate the two parts now The release cam shaft is one of the critical cleaning and lubrication points in the Pentax The release cam shaft must spin freely within the speed selector hole Why Because the release cam rotates as the opening curtain crosses the focal plane aperture Any part which turns with the curtain movement must be able to travel freely Otherwise you ll get erratic curtain movement It s the speed selector hole that gives the eccentric move ment to the release cam as you change the speed setting that s how the speed selector repositions the release cam for different slit widths The edge of the release cam then strikes the end of the closing curtain latch Fig 118 to free the closing curtain Also locate the upper end of the retard rod in Fig 118 This end passes through the hole in the slow speed coupler Figure 119 Bottom of speed selector Fig 119 Another lever the slow speed cam follower Fig 119 rides against the slow speed cam in the speed selector cam stack SLOW SPEED CAM FOLLOWER SEE A SLOW SPEED MOLE n SLOW
160. wl Now hold down the spacer And connect the straight end of the ratchet pawl spring to the post on the counter dial ratchet pawl Fig 141 Once you ve connected the spring the parts may not want to stay in place So you may have to continue holding down the shoulder spacer Then sneak the support shaft assembly into place Use the support shaft assembly to hold down the counter operating parts OPERATING THE SHUTTER WITH THE WIND LEVER PARTS REMOVED You can still cock and release the shutter to check the operation even though you ve removed the wind lever parts Insert a large screwdriver into the screw above the wind shaft gear Fig 142 Then using the screwdriver rotate the wind shaft gear a full turn clockwise that cocks the shutter Release the shutter by first depressing the transport latch Fig 143 and then disengaging the opening curtain latch Try slowly cocking the shutter while watching the transport pawl Fig 143 Near the end of the wind cycle the transport pawl swings toward the transport gears The transport pawl drops into a notch at the bottom of the lower transport gear The transport pawl takes up any backlash in the mechanism So when you allow the wind lever to return the transport gears won t back up turn in a clockwise direction too far ADJUSTING THE COUNTER ADVANCE ACTION Unlike many cameras the Pentax has no forming or ec centric adjustment for the counter advance actio
161. y contains the spring loaded counter shaft Remember the counter dial mounts to the up per end of the counter shaft Fig 134 A gear on the bottom of the counter shaft engages the mechanism which advances the counter dial You can see the counter shaft gear by looking through the support shaft clearance hole Fig 134 Notice that a pinion engages the teeth of the counter shaft gear The pinion ad vances the counter shaft gear each time you cock the shutter While looking through the clearance hole try opening the camera back You can then see how the pinion moves away from the counter shaft gear Fig 135 Disengaging the counter shaft gear allows the spring loaded counter shaft to return to its starting position You won t lose the initial tension of the counter return spring when you remove the support shaft assembly Nor will you disturb any timing But there is one danger removing the support shaft assembly may free the counter advance parts in the camera body P7 assembly Take out the three screws shown in Fig 135 two countersunk screws and the spring mounting screw which sup ports the shutter cocked indicator spring r As a precaution hold your hand over the wind lever end of the camera body And slowly slide out the support shaft assembly If the counter advance parts do come out they at least won t go too far Fig 136 shows the counter advance parts in the camera body The counter dial ratchet pawl has a torsio
162. you ll need the closing curtain latch installed You can then simulate the lat ching action of the closing curtain Temporarily seat the closing curtain latch over the mechanism plate post You don t have to replace the retaining nut Nor do you have to connect the closing curtain latch spring Now use your thumb to turn the closing curtain winding roller in a counterclockwise direction That winds on the clos ing curtain Continue winding on the curtain until the lead edge of the closing curtain bar aligns with your scribe mark the scribe mark you made prior to disassembly While holding the closing curtain winding roller seat the closing curtain wind gear as shown in Fig 178 Notice the posi tion of the latching lug in Fig 178 it points to the small hole in the mechanism plate Now swing the closing curtain latch into engagement with the latching lug as shown in Fig 179 The lead edge of the closing curtain bar should still be aligned with your scribe mark Fig 180 What if it s not Then you have to change the timing between the closing curtain wind gear and the closing curtain winding roller pinion Fig 179 Lift the closing curtain wind gear slightly just enough to disengage the closing curtain wind gear from the closing curtain winding roller pinion Then rotate the closing curtain winding roller in one direction or the other to align the bar with your scribe mark Turn the closing curtain winding roller clockwise
163. you need a faster shutter speed to correct the ex posure And as you ve seen setting a faster shutter speed decreases the resistance of the speed resistor More current flows through path 2 equalizing the two currents Or you can set a smaller f stop to correct the overex posure indication Setting a smaller f stop decreases the resistance of the diaphragm resistor So once again you ve decreased the resistance in path 2 of the circuit A little later we ll go through the actual troubleshooting steps for the circuit shown in Fig 37 But from what you ve seen so far you should be able to draw some general conclu sions For example suppose the needle always shoots to the top of the screen You can then suspect a problem in path 2 If the needle always shoots to the bottom of the screen you can suspect a problem in path 1 What if the needle doesn t move at all If the needle stays centered there s no current in either galvanometer coil Most likely the circuit isn t getting power Or perhaps the galvanometer itself is defective THE PHOTO SWITCH You ll notice that the circuit of Fig 37 has no on off switch Yet we mentioned earlier that the K1000 has an elec tronic on off switch a switch that automatically turns off the meter when the light level drops below EV2 at ASA 100 Fig 39 shows the electronic photo switch added to the basic circuit The photo switch adds only four components to the basic circuit

Asahi Pentax K-1000 Service Manual

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