Home

3600-GTO-2011-0531-w.. - Astro

1. This is the point where they suddenly get very tight Do not exert a lot of pressure on the hex wrench at this point simply reach the point where the screws suddenly tighten up Now repeat the movements you made above The two axes should be stiff but moveable For normal operation you will probably want the clutches near this level of tight ness or just a little tighter Once this bottomed out state is reached there is very little remaining in travel of the clutch adjustment screws Beyond this point very small turns of the hex wrench result in large increases in clutch system tightness If you proceed to mount up and balance your telescope you can feel what this resistance in R A and Dec move ment backwards and forwards is like when you make these motions from the eyepiece end of your telescope as you 26 would during normal use when slewing pushing by hand to acquire an astronomical object within the field of view of your finder or scope How tight can the clutch be and can you do any damage by pushing against them This clutch system is considerably different from that found in the 900 and 1200 series of mounts There are no Delrin clutch plugs Instead the 3600GTO clutches are of a design similar to those in the Mach1GTO only on a much larger scale They can be made quite tight However remember The clutches are much more than a convenience for balancing the system Your objective is not to lock the a
2. the microprocessor chip located in the servo drive box will send continual R A and Dec coordinate data via the cable connections O O O to your computer When you use the software to give instruction to slew to a 9 8 7 6 new object the commands R A and Dec coordinates are sent to the mount Please read the section that follows entitled Controlling Your GTO Mount AE tonsea Dive 3 Transmit from Computer to Servo We provide two RS 232 serial port connections on the mount so that you can 4 Empty use two software programs simultaneously in addition to any auto guider 5 Ground software that may be sending signals to the mount through the Auto guider S a Ready Connector For instance you can use PulseGuide for advanced mount 8 Empty control while using TheSky as a planetarium program The telescope control 9 Empty functions of TheSky are more limited so using both in a remote application is advantageous Since the mount will update the R A and Dec coordinates Pins 2 3 5 amp 6 are active simultaneously both programs are continually updated with the data from the mount You can watch the screen display of TheSky to see where your telescope is pointing as it slews This is most effective if you have a reasonably fast computer with plenty of RAM Please note The two RS 232 ports are NOT identical For high demand applications like the Astro Physics ASCOM V2 Driver we recommend using the top port on your GTO Cont
3. Me as y A fe Ding storne l ast RO PHYSICS Ind 11250 Forest Hills Road _ Machesney Park IL 61115 Telephone 815 282 1513 Fax 815 282 9847 _support astro physics com www astro physics com May 31 2011 _ ASTRO PHYSICS 3600 GERMAN EQUATORIAL WITH GTO SERVO MOTOR DRIVE CONTENTS ABOUT THIS MANUAL MODEL 3600GTO PARTS LIST MODEL GTOCP3 MECHANICAL SPECIFICATIONS GTO SERVO DRIVE SYSTEM PRECISION ENCODER AND LIMIT SWITCH SYSTEMS OPTIONAL INTRODUCTION Why Polar Alignment is Important ASSEMBLY DIAGRAM INITIAL MOUNT ASSEMBLY AT YOUR OBSERVING SITE OR OBSERVATORY Assemble Pier or Attach 3600 Flat Surface Adapter to your Existing Permanent Pier Assemble Polar Axis Assembly to Pier and Attach Azimuth Adjuster Prepare to Mount the Declination Axis Mount the Declination Axis onto the R A Axis Attach the GTOCP3 Control Box optional GTOELS Limit Switch Encoder Box and Cables FINAL ASSEMBLY CABLE MANAGEMENT AND POLAR ALIGNMENT Attach Mounting Plate Astro Physics 22 Dovetail System Astro Physics PlaneWave Dovetail Saddle Plate Additional features of the DOVE3622 SB3622 SB3627 DOVEPW and DOVELM162 Cable management Mount Control Cables Servo Limit Homing Switch and Precision Encoder Accessory Cables Specific Instructions for Routing Your Auxiliary Cables Polar Alignment Part 1 Rough Alignment Altitude and Azimuth Adjustments Rough Polar Alignment The Azimuth Adjustment System The
4. plagues so many imaging systems controllers and other accessories TERE SS ee ee amp S E Cable Channels under the DOVE3622 DETE PLTTIRT a The next steps in the cable routing path are the two cable channels eee underneath the DOVE3622 Dovetail Saddle Plate These channels DES Ver provide adequate space for the cables to be routed to the center of the declination axis where they enter the mount itself The DOVE3622 saddle plate should be mounted with the cable channels on the eyepiece camera end of the optical assembly rather than at the objective end The bottom of the DOVE3622 has also been drilled and tapped for the addition of a custom cable port plate if you wish to have one made See photo below DOVE3622 Underside Mounting Holes for Custom Cable Port Plate Cable Channels under the DOVEPW The DOVEPW also has cable channels on its underside The channels are a bit smaller than on the DOVE3622 but they are found both on the front and back of the plate There is no provision for a custom cable port plate on the DOVEPW 18 Route cables through the mount and out the R A Rear Cover Plate The cable channels provide unobstructed access to the hollow center of the declination axis Cables pass through the top half of the declination axis and are then routed through the opening in the Dec R A Mating Surface and from there into the hollow center of the R A axis The R A Rear Cover Plate has three ca
5. tee ok F i s S Altitude m X Adjuster 6 Hand Wheel GTOELS optional 3600 Flat _ Pi Surface Adapter optional Azimuth Adjuster R A Rear Cover Plate ees Limit Switch Connector optional Servo Panel Encoder Limit Servo Connector Switch Panel to GTOCP3 Rear Sight Hole Cover Encoder Connector optional Mount Base with Integral Precision Adjust Rotating Pier Adapter Plate Mounting Holes for Auxiliary and Azimuth Adjuster Block 3600 Flat Surface Adapter lt F Panel or Pier Top 7 tapped 3 8 16 INITIAL MOUNT ASSEMBLY AT YOUR OBSERVING SITE OR OBSERVATORY Assemble Pier or Attach 3600 Flat Surface Adapter to your Existing Permanent Pier The 3600GTO will be carrying many pounds and many thousands of dollars worth of equipment all the while performing at levels measured in arc seconds and fractions of arc seconds To achieve the mount s potential level of performance it must be on a solid and secure pier e Apermanent pier with a deep footing and a flat surface on top is highly recommended for an observatory situation We suggest that for ease of installation the pier should incorporate a 12 to 16 diameter top plate of steel or aluminum that is drilled and tapped with eight 3 8 16 holes ona 10 788 bolt circle as shown in the drawing at right Then simply bolt the 3600 Flat Surface Adapter 3600FSA to the top for a perfect fit Alternatively your permanen
6. Imaging software that uses the ASCOM interface e Any other ASCOM compliant software including several products from CCDWare which include PEMPro see below PEMPro V 2 x latest release by Sirius lmaging Included with the 3600GTO For a visual observer or an imager who takes short exposures the native performance of your 3600GTO will be superb without additional periodic error correction However those of you who take long exposure images may wish to further refine your mount s performance This may be especially important if your images are unguided PEMPro Periodic Error Management Professional is a Windows software application that makes it easy to characterize and reduce periodic error PEMPro gives you powerful tools to program your mount s periodic error correction firmware to achieve the best possible performance for your mount PEMPro dramatically improves guided and unguided imaging resulting in better images and fewer lost exposures PEMPro will analyze the performance of any mount that is equipped with a CCD camera and compatible camera control software Compatible CCD camera control software includes CCDSoft version 5 00 170 and later MaxlmDL CCD version 3 22 and later and AstroArt V3 SP3 and later PEMPro V2 also provides a way to use a low cost webcam or video camera to perform all of its functions PEMPro V2 has a Video interface application that can work with any DirectShow or WDM complia
7. SHCS for attaching the SBDAPB or LMAPBLOCKS 1 4 20x1 1 4 FHCS for attaching directly to AP Rings 1 4 20x3 8 SHCS for Safety Stop SBDAPB AP Riser Spacer Blocks 4 10 32 x 1 2 SHCS for attaching to mounting ring tops ae Blocks for large Taks Mewlon BRC amp i mioz 20mm SUCS ifor attaching te SBD 16 SBD13SS or 13 or 16 Side by side Dovetail Plate for SBD16SS Losmandy D Series Dovetail Saddle Plates SB0800 or 7 and 10 Sliding Bars for DOVE08 or ACPLTR SB1000 or and SB1500 15 Sliding Bar for DOVE15 12 Sliding Bar for the Losmandy D Series Dovetail Saddle Plates 16 x 5 Wide Sliding Bar for the Losmandy D Series Dovetail Saddle Plates _ ee ee ee SS 2 1 4 20x3 8 SHCS for Safety Stops required at both ends 12 Losmandy D Series Male to Vixen Style 1 1 4 20x1 4 low profile SHCS to replace Safety Stop on V plate Losmandy V Series Female Adapter Sliding Bar 1 1 4 20x1 4 SHCS Safety Stop for SBD2V 5 16 18x5 8 SHCS Losmandy Tripod to Astro Physics Mount Adapter 1 4 20x5 8 SHCS Screw Key Plate 1 4 20x1 SHCS length length length 3 8 16x3 4 SHCS LT2APM N N W W W EEEIEE lt Uw control on mazoxsarnscs Oww Chow Cmn Bi Level Su es g 1 4 20X1 FHSCS Flat Head SocketHead Button Head PP 5 16 18X1 BHSCS Socket Cap Cap Screw Socket Cap Single Level Support Bar 5 16 18X3 4 BHSCS Screw FHSCS SHCS Screw BHSCS 16 5 Dovetail Saddle for
8. With that in mind in the future if you need to add a cable you simply do the following a Tie the new cable end and a new identical piece of string to the end of the string protruding from the declination axis Sometimes it is easiest to fold the cable end back on itself and tie the strings at the bend in the cable b Cover the cable end and string knots with wrapped tape in such a way that there is no longer a snag at the place where the cable end and strings come together If you have some electrician s wire pulling soap apply a small 19 10 11 12 13 amount to the taped knot as lubrication Do not lubricate with anything that is not safe for electrical insulation c Grab the string end that protrudes from the R A axis and pull gently as you guide and push the new cable string bundle through the declination end You may need to jiggle a bit as the cable end rounds the corner inside the mount but in this way you should be able to add a new cable to a fully set up system d When the cable end is pulled out of the R A axis untape and untie everything Your new cable will be through the mount You will have a new string in place for any future additions And you can save the old string for next time e If your cable gets stuck it will almost certainly be at the corner where the cable must leave the Dec and enter the R A axis If needed remove the R A Rear Cover Plate to reach up and help it thr
9. usable Stainless counterweight shaft 2 5 dia with machined black anodized safety stop Y cable for internal cable routing R A portion is 19 5 long and Dec portion is 35 long inside R A 22 Servo Extension Cable for connection to GTOCP3 Control Box D C power cord cigarette lighter adapter on one end 8 long Straight through Serial Cable 15 feet long for connection to computer GTO Keypad controller with 15 coiled cable Instruction Manual and installed Keypad Protector KEYPRO 3 8 16 x 3 4 socket cap screws with seven 3 8 ID x 7 8 OD flat washers for attachment to pier or 3600FSA Hex key set with additional 3 8 long arm hex key Var Cable stays some attached Velcro straps 1 keypad lanyard strap etc 1 PEMPro V 2 x Full Version Periodic Error Management software with Polar Alignment Wizard CD ROM 1 PulseGuide by Sirius Imaging remote control utility for improved guiding CD ROM a VN SA aa l a a a H i M a In order to fully assemble your mount you will need the following items sold separately e Telescope mounting plate We recommend our 22 x 12 9 Dovetail Saddle Plate DOVE3622 and the 22 x 9 9 Dovetail Plate SB3622 or 27 x 9 9 Dovetail Plate SB3627 We also have a 16 5 Dovetail Saddle Plate for PlaneWave Instruments Scopes DOVEPW e Pier Permanent Pier 12 minimum diameter recommended 12 O D ATS Portable Pier or other pier e 3600 Fla
10. you will need to start by lowering the altitude enough to sight your mark through the sight hole Loosen the four Polar Axis Lock down Bolts as described above and turn the Altitude Adjuster Hand Wheel clockwise until the altitude angle will allow you to see your mark If you are using a compass you can skip this step 4 Make azimuth adjustments until your reference point or plumb line is centered east to west in the sight hole If using a compass adjust until it is pointing to true north magnetic north adjusted for the magnetic declination at your location Be sure to snug the backed off Azimuth Adjuster Knob against the Azimuth Adjuster Block when you are finished 5 Make altitude adjustments If you skipped step 3 above loosen the four Polar Axis Lock down Bolts now Turn the Altitude Adjuster Hand Wheel counter clockwise to raise the altitude clockwise to lower it For higher latitudes a simple small flat mirror 2 x 2 is a good size can be employed as a simple diagonal to sight in on the pole A 1 25 diagonal will also fit into the sight hole but be careful i a Fa that you will be able to remove it once your altitude is set The Rough Polar Alignment photo at right shows a flat mirror being employed at a latitude of just with a over 55 degrees OK OK I confess That isn t really Polaris in Small Flat Mirror the mirror cheated for the photo but have tested the technique outside under the stars and it w
11. 1 OOO Go oO oO 2 O OQ 1 4 thru holes with 5 500 and 7 450 crosswise spacings for custom applications Lengthwise spacing interval is alternating with three holes at 0 500 and then a 1 00 interval then three more and so on 6 031 8 220 O O O 1 4 thru holes with 3 500 crosswise spacing for rings having the Losmandy spacing Lengthwise spacing interval is alternating with three holes at 0 500 and then a 1 00 interval then three more and so on 50 27 DOVETAIL SLIDING BAR DRAWING SB3627 for attaching to the 3600GTO Dovetail Saddle Plate DOVE3622 1 4 thru holes with 5 500 and 7 450 5 16 thru holes with crosswise spacing crosswise spacing are available for at 4 500 for largest AP rings i e for custom applications Lengthwise kam een WU NOG WIIN 2 200 Riccardi Honders and for DOVEPW in 180 mm lengthwise spacing for spacing is at the standard 1 375 for to 3 500 Tose wiae Spacing for side by side arrangement Lengthwise Takahashi Mewlons BRC and the 5 5 sets and is doubled up at AP rings 3 200 and rings with spacing is 1 375 FRC 5 sets 0 688 for the wider cross spaced ai oe aad 3 500 mounting holes 4 921 1 3 937 100 25 O O O O O O OOOOOQOO0OO0O 0OO0OO i Q 1 4 20 tapped holes with 8 220 crosswise Takahashi 10 mm thru holes with spacing used for locking SB3627 to the 100 mm and 125 mm c
12. Altitude Latitude Adjuster Procedure for Rough Alignment The Daytime Polar Alignment Routine in Brief Attach Counterweight Shaft and Counterweights Attach Mounting Rings and Scope Understanding the R A and Dec Clutches Balancing Your Telescope First Balance the Declination Axis Second Balance the Polar Axis Polar Alignment Part 2 Fine Polar Alignment Tips on Making the Fine Adjustments to the System Methods for Fine Polar Alignment MOON DO A a oa amp W a a AA N O Ql gt a oe a NOOO OO WO o o OC NOM NM NN NH RWWhHDN NO N N O O o ONN NNN OO O o POWER CONSIDERATIONS Introduction Some Power Basics for Non Electrical Engineers Batteries Results of Either Inadequate or Excessive Power SERVO MOTOR DRIVE THE BRAINS OF YOUR MOUNT GTO Control Box Model GTOCP3 Pre loaded PEMPro Curve Lead Free ROHS compliant Electronics R A and Dec Cable 10 pin Receptacle 12V Locking Receptacle POWER Indicator Light KEYPAD Receptacle RS 232 Ports 2 FOCUSER Jack RETICLE Jack 1 6 to 4 6 volt variable output AUTOGUIDER Port Receptacle 6V Auxiliary Jack N and S Switch Drainage Holes CONTROLLING YOUR GTO MOUNT GTO Keypad Operation PulseGuide by Sirius Imaging The Astro Physics ASCOM V2 Driver Planetarium Imaging and Observatory Software from Other Vendors PEMPro V 2 x latest release by Sirius Imaging The Astro Physics Command Center APCC OPTION
13. And it is why we recommend using the relatively short heavy duty Kendrick Alligator Clip KDRALL or something similar for connections to a battery system Keep this in mind when choosing your components To say that the power delivery system that you employ is only as good as its weakest link is not quite adequate to the truth In reality the power supply system will be degraded by the sum total of all its individual weaknesses So what are the DO s and DON T s e DO NOT use power supplies designed for portable stereos laptop computers or other consumer electronics e DO NOT use the supply from a Meade or Celestron system even though they may claim to provide adequate power e DO NOT power additional devices from your mount s power source especially dew heaters which are notorious for initiating momentary voltage dropouts as they cycle on and off The auxiliary GTOELS control box for the Precision Encoder System and software control of the Limit Homing Switch System can be powered from the same source as the mount e DO NOT use a DC extension cord between your DC power supply and the Mount s power cord Run any needed extension cords on the AC side if possible or move your battery pack closer to the mount e DO NOT use batteries or battery packs with less than 30 amp hours of power In fact we would recommend nothing less than a large i e 50 amp hour deep cycle marine battery See section below e DO give
14. Encoders Mounted shaft encoders for use with digital setting circles can not be used with the 3600GTO They are not needed since the go to functions of the mount are so much more accurate The encoder that is built into the servo motor itself has a resolution of 0 05 arc seconds vs 324 arc seconds for mounted encoders Do not confuse shaft encoders with the Precision Encoder System that is an option with the 3600GTO mount The Precision Encoder System which is detailed later in this manual is for real time periodic error reduction MECHANICAL SPECIFICATIONS 13 0 330 mm 256 tooth aluminum Brass 1 41 35 8 mm diameter Axis shafts R A Dec 4 72 120 mm diameter with 4 02 102 mm clear inside diameter Shaft axis bearings R A Dec 7 09 180 mm diameter deep groove ball bearings Worm Gear Bearings R A Dec 1 57 40 mm angular contact ball bearings Latitude range 15 70 degrees Azimuth adjustment Approximately 14 degrees 7 degrees from center 2 5 63 5 mm diameter x 31 5 800 mm long 30 762 mm usable length Counterweight shaft Includes large machined safety stop knob Will fit twelve optional 30 Ib 13 6 kg counterweights Optional 10 254 mm shaft extension available Total 247 Ib 112 kg R A axis polar fork 121 Ib 55 kg Dec axis 84 Ib 38 kg Counterweight shaft 42 Ib 19 kg Conservatively rated for 300 Ib 136 kg instrument weight scope and accessories
15. If you own more than one instrument you Dec Hub outside Bee OTTE i diameter 13 y2 4 9 09 may want more than one sliding bar so that you do not need to detach the plate from one instrument in Lock down holes for SB3622 SB3627 order to use another The Dovetail Sliding Bars are extremely versatile and can be used with a wide variety of large instruments You can also configure side by side setups using our 16 Dovetail Saddle Plate for Losmandy D series plates DOVELM162 and or our 16 5 Dovetail for PlaneWave DOVEPW see below Unfortunately you cannot use our previous versions of the 16 Dovetail Saddle Plate DOVELM16 or DOVELM16S on the SB3622 and can only use them on the ends of the SB3627 The 22 Dovetail Saddle Plate DOVE3622 The DOVE3622 can be mounted in any of three positions depending on the balance point of your instrument s The plate has circles inscribed in its top surface to help ee you line up the appropriate sets of holes for attachment If you start by lining up the holes in the center safety slot Cable along the optical axis as shown in the drawing above then the rest of the available holes will all line up for your chosen position forward centered or back The actual process of balancing your setup and using the clutches is detailed later in the manual As described in earlier instructions it is best to get all of the bolts started first then snug them all in a criss cross patt
16. Physics lam experiencing trailed stars after a slew and apparently a high variable backlash Check to make sure that the spur gear that is attached to the end of the worm is not loose A loose screw will indeed cause the axis to delay during reversal In a few cases we have seen that the set screw on this spur has backed off and needs to be retightened If you have any doubts about where this worm and spur gear is in the scheme of things call Astro Physics and we will talk you through the procedure to check this Remember this Any backlash or looseness in Dec will NOT cause trailed stars after a slew That is because the Dec axis does not move once it gets to its new position so no trailing is possible So if you are getting trailed stars for a short time don t look for something in the Dec axis However the R A axis WILL cause trailed stars after a slew if the spur gear is loose That is because this axis must move at the sidereal rate immediately after getting to the new position If the spur gear is loose on the worm shaft it will turn slowly at the sidereal rate without imparting this motion to the worm itself because it is slipping At some point the set screw will catch on the edge of the flat on the worm shaft and begin to drive the worm gear So this looks like classical backlash when in fact it is not backlash at all and all attempts at setting the gear mesh on the worm are futile to correct this lost motion When we get a
17. and assembly of our mounts to alleviate this problem but it is still a good idea to periodically once or twice a year inspect and if necessary re tighten any easily accessible fasteners Additional maintenance information can be found below in the troubleshooting section and in the Technical Support Section of our Web site ADDITIONAL TIPS AND SUPPORT For additional information regarding the 3600GTO refer to the Technical Support Section of our Web site We also encourage you to participate in the ap gto user group The members of this group are very knowledgeable about the operation of their mounts CCD imaging and other related issues Since the GTO Servo Drive electronics are common to all of our GTO mounts you can benefit from the wisdom of many experienced users on this group The staff of Astro Physics also participates and you will find a wealth of information in the archives To find the group link from User Groups in our Web site s sidebar We encourage you to submit your technical support questions directly to Astro Physics by phone or e mail support astro physics com 44 TROUBLESHOOTING Additional troubleshooting questions are in the GTO Keypad manual Some of the issues discussed in the keypad manual relate to mount communication issues whether you use the keypad or control the mount with a planetarium program or PulseGuide Please refer to them The Declination or R A axis is fairly tight even with the clutch set s
18. as you observe through the eyepiece or take astrophotos Please study the sections detailing polar alignment procedures later in the manual 6 ASSEMBLY DIAGRAM The following terms and abbreviations are used interchangeably in these instructions Polar axis right ascension axis R A axis R A housing Declination axis Dec axis Dec housing Please read all instructions before attempting to set up your 3600GTO mount The model 3600GTO is very rugged however like any precision instrument it can be damaged by improper handling Please refer to the diagram below for an illustration of the mount The parts are labelled so that we can establish common terminology Your 3600GTO comes with an integral pier adapter which includes the azimuth adjuster block We recommend the optional 3600 Flat Surface Adapter S3600FSA for most installations Declination Declination Limit Homing Switch amp Motor Gearbox Actuator optional Declination Clutch Adjustment Screws 3 Declination R A Cable Covers R A Limit Homing Switch amp x Actuator optional Declination Portion of Servo Cable Front son 9 3 Hole Cover R A Motor Gearbox R A Clutch Adjustment Screws 3 Declination Attachment Bolts 6 Polar Axis Lock Down Bolts Counterweight Shaft Polar Axis lt __ Pivot Bolt Polar Fork Assembly Servo Extension i AE Cable B GTOCP3
19. at least 6 amps at 15 volts continuously available to it to ensure that it is adequately energized A power supply that can deliver 10 amps would have the reserve capacity to deliver steady power through any peaks in demand such as when new movement is initiated and acceleration is underway You must also understand that voltage and amperage are not independent of each other If your mount demands more current amps than your power supply can deliver the result will be a drop in the pressure or voltage of the current A power supply of insufficient current or amperage capacity cannot maintain the pressure or voltage when a system demands excess current even if only momentarily A lower voltage power supply will need more available amperage than a higher voltage supply This is easiest to understand if you remember that the work done or energy converted into work measured in watts is always equal to the volts times the amps Imagine a water wheel that must turn a mechanical device A small stream of water at high pressure will turn the wheel but so will a large volume of water at low pressure If you are inside the building watching the device operate you can t tell whether the wheel is being turned by a small volume at high pressure or by a large volume at low pressure To further illustrate we tested a 3600GTOPE in our shop using a variable power supply and recorded the current load at several voltages The mount was at room temperature and
20. drained and re charged many times without suffering a loss of capacity as happens with typical car batteries t8 V Another excellent battery choice is to purchase 6 or 8 volt golf cart batteries that are then wired in series A single 6 volt battery of similar amp hour rating could be wired in series to a 12 volt deep cycle marine battery to produce 18 volts or three 6 volt golf cart batteries could be wired in series to also produce 18 volts Since golf cart batteries are also available in 8 volt sizes two of these wired in series would yield a perfect 16 volts for your mount Be aware however that there are limitations in available charging systems Eight volt batteries are normally used with three batteries in series to create a 24 volt system and are charged accordingly To use 8 volt batteries you might need to purchase 3 batteries and use them in rotations of 2 for each session 34 All of the lead acid based batteries whether traditional flooded or wet non sealed where you add distilled water periodically gel or AGM will basically measure about 2 3 volts per cell when new and fully charged In an actual operating circuit the output of a fully charged battery cell is closer to 2 1 volts per cell Therefore the standard 12 volt battery when new and fully charged will measure 2 3 volts x 6 cells 13 8 volts with no load applied and will measure about 12 6 volts under a normal load of several amps Likewise a so ca
21. drilled slotted or even fitted with receptacles if you so desire The other cable covers can also be modified to meet your needs We look forward to seeing some of the clever solutions that you develop Remember to adjust the altitude back up to your latitude as close as you can get before loading the mount up with instrument and counterweights 20 Polar Alignment Part 1 Rough Alignment We recommend that you accomplish your polar alignment in two or more phases rough alignment and fine alignment or successively finer alignments The purpose of performing a rough alignment before final system assembly is to minimize the amount of adjustment that is necessary once the mount is fully loaded with equipment and counterweights NOTE A polar alignment scope cannot be used with the 3600GTO There were a number of considerations that made a polar scope impractical for the 3600GTO e The mount s polar fork geometry and rear altitude adjuster would interfere at all but the lowest latitudes e A huge sight hole would have been required on the top of the Dec axis to avoid vignetting of the alignment stars around the periphery of the polar scope Oo wl e Internal cabling would interfere with the operation of the Si PP FEE es ighting Polaris through polar scope i Polar Alignment Sight Hole g g e An externally mounted polar scope i e on a bracket on Mount shown is a 900GTO the side of the axis d
22. driving the worm gear but that your clutches might have been loose and therefore the scope was not following the motion of the worm gear The fact that the high slew rate did move the scope does not change this because Roland has seen this himself where the tracking rate did not overcome the slipping clutches but the slew rate did If you are unsure of the motion of the motor just remove the motor cover plate and look inside You will see the motor turning Sometimes when you have the clutches loosely engaged and the counterweights are somewhat out of balance being heavy in the east then the clutches might slip at the slow sidereal rate In any case just to set your mind at ease simply remove the motor cover next time something like this happens and look at the motor shaft If the motor is not turning you will have some kind of electrical problem If it is turning then it is mechanical The motors sound louder and more labored in cold weather As the temperature drops we recommend that you reduce your slewing speed to the slowest slew rate The cold causes the lubricants to get stiff in the gearboxes This can make the high speed gears resonate and sound screechy Lowering the slew speed in winter will eliminate this You might also want to add a drop or two of light machine oil to the center posts of the individual gears Just remove the cover on the gearbox and add the oil drops The noise is nothing to worry about Refer to the section of t
23. during 1 minute or so and is accumulated over time so it doesn t look like periodic error The sidereal tracking rate is exact in the mount it is crystal controlled and checked here for accuracy However the stars do not move at exactly the sidereal rate everywhere in the sky The only place they move at that rate is straight overhead As soon as you depart from that point in the sky the stars will be moving more slowly especially as you approach the 45 horizons Thus it looks like the mount is moving slightly faster than the sidereal rate Just because you have done a classic drift alignment does not mean that the stars will now be moving at the sidereal rate everywhere in the sky In order to increase the area of sky from the zenith that will give you fairly good tracking you will need to offset the polar axis by a small amount The amount will depend on what your latitude is The other approach is to vary the tracking rate for different parts of the sky Ray Gralak s Pulse Guide will allow you to dial in an exact tracking rate for any part of the sky The Astro Physics Command Center APCC includes tracking and pointing correction based on calculations from atmospheric refraction all the way up to sophisticated real world models based on plate solve data for your specific instrument package Initially the mount was working fine Then suddenly the mount stopped tracking altogether Chances are that the motor was turning properly and
24. expensive servomotors in case of severe overload on the two axes The primary cause is an unbalanced load in R A If the extra load opposes the motor rotation the motor must work harder to track at the sidereal rate and the current will rise to high levels If the current exceeds the trip point for more than a minute the logic will shut the motor off and tracking stops It typically takes about 8 ft Ib of unbalance to trip the overload but a very heavy load of scopes accessories and coun terweights on the mount can decrease this unbalance threshold 2 The voltage of your power source has probably dropped too low See the earlier section on power considerations 3 The current rating of your AC DC power supply is too low Additional explanation During slewing the two motors can draw up to 6 amps from a typical 12 volt source Using our recommended 15 volt supply will reduce this amperage draw However the amperage may increase when the temperature approaches freezing or below It is recommended that your supply be rated at from 6 to 10 amps 12 volts DC minimum 14 to 18 volts recommended 20 volts max We highly recommend our 15 Volt 10 Amp Sup ply PS15V10AC If you also power other equipment CCD cameras dew heaters etc from the same source you will need a supply capable of over 10 amps or better still multiple power supplies The more equipment you have the more current capability you will need For portable applications we rec
25. of all our mounts we have developed and now fully support a V2 ASCOM Driver for use with all ASCOM client software As mentioned above we also include PulseGuide mount control utility software and a full version of PEMPro Periodic Error Management Professional v 2 x latest version for you to enhance your control and performance options As an added bonus all 3600GTO mounts will come pre loaded with the custom fitted PEMPro corrections from our extensive individual testing that is performed on each and every mount While the native periodic error of your 3600GTO will be 5 arc seconds or less you can reduce it even further to maximize performance without auto guiding These software control products are detailed later in the manual In addition to everything outlined above the 3600GTO s control and performance options will be greatly enhanced by the upcoming Astro Physics Command Center APCC This exciting software is in the second phase of beta testing at the time of this writing and the final release will be supplied at no additional charge to owners of the 3600GTO APCC will fully address the extended capabilities of the 3600GTO including the optional Limit Switch and Precision Encoder Systems The 3600GTO is most at home in a permanent observatory but unlike most observatory class mountings it can go portable for remote star parties if you have a large enough vehicle and a couple of strong friends to assist you This mount
26. required dimensions for pier top design Top of adapter Mount fits inside Bottom of adapter Mates to flat pier top Northern Hemisphere Southern Hemisphere ae es raced al45 _ 1 spac 4 i 5 a Co aS tg ee Ung x F GT 4 a l _ ae A s T meter TES rit ne Da me Oa e e Gt 6 ae gt Gounter b red aT thru holes forie T hy ar Bie balls for 1200SPA a f E Side thru holes for 3 8 bolts for mount attachment 8 0 500 Top to center of side thru hole _________ 49 y Outside diameter z Ene s round as modern CNC machining can achieve The 3600 Flat Surface Adapter is likewise machined to precise CNC tolerances The two components mate perfectly without either undue resistance or slop Experience has taught us that trying to get a good fit in an open pipe pier top is virtually impossible due to out of roundness and or variable wall thickness Assemble Polar Axis Assembly to Pier and Attach Azimuth Adjuster In order to track the motion of astronomical objects the polar axis must be positioned so that an imaginary line drawn through the center of the axis points toward the celestial pole Refer to the diagram at the front of this manual for a graphical representation At this stage of the assembly process you want to position the mount so that it points roughly north 1 Orient the pier Set your pier up so that th
27. set To adjust the altitude these two bolts must be loosened on each side 4 bolts total The bolts do not need to be extremely loose and should not be removed Infact when performing your final fine alignments they should be snug to avoid any shifting that may result from re tightening them Loosen The altitude is adjusted by turning the Altitude Adjuster Hand Wheel The a Hand Wheel has a folding handle To unfold the handle for altitude Center Pivot Balt adjustment pull up on the handle and then simply fold it out as shown in the photo Turning the Hand Wheel counter clockwise will raise the altitude turning it clockwise will lower the altitude One full turn of the Altitude Adjuster Hand Wheel is approximatel 0 37 degrees 22 arc minutes Once you have reached your desired altitude setting tighten the four Polar Axis Lock down Bolts and fold the handle back into the Hand Wheel Procedure for Rough Alignment 1 If available use an inclinometer a compass a reference point plumb line or other mechanical device s to help you to get close 2 Remove the Sight Hole Covers from both the R A and Dec axes If you examine the polar axis assembly you will see that the center of the R A shaft is hollow You can sight right up through this hollow shaft and right out the declination axis sight hole if your latitude is not too high 3 If you are using a reference point or plumb line on the north wall of your observatory
28. the gear mesh was set as perfectly as our mount supervisor could do it This mount was equipped with the optional Precision Encoder PE and Limit Switch Systems LSS and their GTOELS box was also powered up through the same variable power supply To give the mount a bit more of a challenge since it was not carrying a heavy load it was set up roughly 4 foot pounds out of balance in declination and about 8 foot pounds out of balance in right ascension The tests were then performed in such a way that the mount was lifting the out of balance side from the same starting position for each test We ignored the downhill slew amperage readings which were slightly lower of course as we reset for each test Please note that the addition of the PE and LSS along with the out of balance setup led to slightly higher overall current draw than is in the mount s specification sheet in the front of the manual and on the Web site This was entirely as expected This mount when unloaded reasonably balanced and without power to the GTOELS box for the PE and LSS drew the expected half amp at sidereal tracking and just under two amps slewing with 15 volts being supplied VoL_TAGE Vs CurRENT DRAW TABLE 24 0 Volts 0 93 Amps 1 85 Amps 21 amp 24 volts used for testing are NOT recommended for normal operation An important thing to note is that above 15 volts the total wattage begins to increase dramatically at sidereal rate This incre
29. to telescopes eyepieces and other equipment in your astro arsenal Cleaning and Touch up Wipe your mount clean with a soft dry cloth If needed you can use a damp cloth or a cloth that has been sprayed with a mild non abrasive cleaner window or all purpose cleaner no bleach Do not spray cleaners directly onto your mount If you use a cleaning product follow with a damp cloth to remove the chemicals from the mount The painted surfaces of your mount may end up with scuff marks from repeated transport and assembly disassembly Most of the time these marks can be removed with a product like Color Back by Turtlewax automotive product Simply apply with a paper towel and buff out the mark If your paint becomes chipped touch up kits are available for purchase please call us NOTE Paint touch up kits can only be sold to U S customers because of regulations governing shipment of hazardous materials Routine Mount Maintenance Under normal operating conditions minimal maintenance is required If the R A and Dec axes are attached together for a long time in outside conditions i e in a permanent observatory then the mating surfaces should be lightly oiled or greased if you expect to get them apart again after 10 years Jostling and vibrations associated with transport to and from observing sites has had the effect of causing screws and fasteners to work their way loose over time We have worked very hard in both the design
30. will reverse The servo controller must be power cycled i e the power cord must be removed and re attached to make this work Drainage Holes Two holes are drilled into the lower portion of the bottom of the control box These holes allow excess moisture to drain from your control box particularly useful on dewy nights Please do not plug or obstruct these holes 39 CONTROLLING YOUR GTO MOUNT Your Astro Physics 3600 GTO has a remarkable servo control system that combines with the precise mechanics of the physical components to give the mount its superb performance Contrary to popular assumption the brains of the mount are not found in the keypad nor are they in an external computer that is used to send the mount pointing here or there The real brains of the Astro Physics GTO Servo Control System are in the GTOCP3 control box Simply think of your keypad or computer as being an input device for the GTOCP3 If you understand this from the start you will always have a better concept of how things work and you will be less likely to make operator errors GTO Keypad Operation Please refer to the manual for the GTO Keypad Controller for complete instructions PLEASE NOTE The slew and top button speeds referred to in the keypad manual of 1200x 900x and 600x are actually 600x 450x and 300x times the sidereal rate for the 3600GTO This difference is not reflected in the keypad documentation nor on the Main Menu display of the keypad itsel
31. your mount its own power source if possible and power other devices from a separate source or sources e DOuse power inverters to go from standard household AC current to DC current that are both filtered and regulated to ensure clean steady power delivery e DO inspect your mount s power cord regularly to be sure that it is not damaged and be sure that the split center pin of the power receptacle on the GTOCP3 or GTOELS control box is spread enough to make good contact with the inside of the cable s locking plug e DO use higher voltages up to 18 to 20 volts for extremely cold temperatures e DO keep an eye on the power LED on your GTOCP3 control box It bears repeating The larger of the two power supplies that we offer is an excellent choice for virtually all customers with U S standard 110 to120 volt 60 Hz AC household current PS15V10AC We have operated the observatory 3600GTO here at Astro Physics for many hours at sub zero temperatures with no power issues from the mount The laptop computer did not fare so well Batteries If you are using battery power be sure that you are using fully charged deep cycle type batteries with an absolute minimum 30 amp hour rating Deep cycle batteries with AGM absorptive glass mat technology are among the best to use as they deliver relatively steady power levels throughout their discharge cycle They are also designed to recover from more extreme levels of discharge and can be
32. 42 SLEWING YOUR MOUNT IN BELOW FREEZING TEMPERATURES There are several potential problems when slewing your mount in below freezing temperatures The symptoms are a wavering or chattering sound from the motors a slowing down of the slewing with a sudden jolting stop at the end of the slew and in the worst case a continuous running of the motors and loss of control The following are three suggestions to alleviate the problem First in cold weather it takes significantly more power to slew the motors than it does in the summer see Roland s tests below This extra current drain can cause a voltage drop in the power cord running from the supply to the CP3 control box It is therefore especially important that you not use extension cords between the mount s cord and the DC power source If you must have a long distance between the supply and CP3 control box unavoidable in some observatory situations use a heavy wire to minimize the voltage drop If the power drops below about 10 5 11 volts at the servo terminal the internal computer chips may reset with subsequent loss of control of the motors If your supply is marginal it may also not produce the voltage necessary for proper operation during slews It is a good idea to limit the slew speed to 300x during real cold weather to reduce the power demand from the supply See the earlier section on power considerations Second it is very important not to have the worm mesh set overly tight O
33. 45 Spacing for 1 4 bolts 3 2 bolt circle tapped 1 4 20 3600GTO Mounting Holes Additional features of the DOVE3622 SB3622 SB3627 DOVEPW and DOVELM162 e The dovetail system can be set up for tip in or slide in of ace l the dovetail sliding bar B3622 Dovetail Sliding Bar with three DOVELM162 Saddle Plates e Safety slots on the saddle plate DOVE3622 coupled with the sliding bar s safety stop will help keep accidents from happening See photo on previous page The DOVEPW has tapped holes for safety stops at each end Top View e For permanent installations a series of matching Lock down through holes in the saddle DOVE3622 and tapped holes in the sliding dovetail plates SB3622 and SB3627 allow the setup to be bolted into its final position through both plates once adequate balance is achieved See photos above for these plates Maximum e As an added feature both the 22 Dovetail Saddle Plate Offset DOVE3622 and the 16 5 Dovetail Plate for PlaneWave Front Back Centered DOVEPW have cable channels machined into the bottom to facilitate through the mount cable routing if desired 1 Increments See photo on previous page and in the next section on Middle plate cable management shown off center e The DOVE3622 has been drilled and tapped on the Ao oy pew pe nd eyepiece end so that youcanattachaplatethatcanbe SOS I aw lt 2 customize
34. AL 3600GTO LIMIT HOMING SWITCH SYSTEM 36LSS OPTIONAL 3600GTO PRECISION ENCODER SYSTEM ON THE 3600GTOPE SLEWING YOUR MOUNT IN BELOW FREEZING TEMPERATURES MOUNT CARE CLEANING AND MAINTENANCE Care Cleaning and Touch up Routine Mount Maintenance ADDITIONAL TIPS AND SUPPORT TROUBLESHOOTING CHARACTERIZING THE DEC AXIS MOTIONS ASTRO PHYSICS MOUNTING PLATE FASTENER CHART 22 DOVETAIL SLIDING BAR DRAWING 27 DOVETAIL SLIDING BAR DRAWING ASTRO PHYSICS 3600GTO El Capitan GERMAN EQUATORIAL WITH GTO SERVO MOTOR DRIVE For Mounts shipped starting in September 2010 and all previous versions ABOUT THIS MANUAL This version of the 3600GTO Manual was prepared for the production run of mounts that began shipping in September of 2010 Most of the information in this manual is applicable to all 3600GTO s that have been produced Some of the information in this manual was simply not available when the first 3600GTO s left our factory back in 2008 This includes information on newer accessories for the mount that weren t available for the first production runs We have also learned a few things through experience and the suggestions of our customers that have improved the information that is available in this manual Please note that we are continually working to improve our products and as a consequence some of the drawings photographs and descriptions found in this manual may not reflect the latest appearance of the pro
35. CHARACTERIZING THE DEC AXIS MOTIONS These instructions explain how to use Maxim DL software as a tool for characterizing any problems with the Declination axis movements of your mount However Ray Gralak s PulseGuide software offers an easier and more extensive evaluation procedure PulseGuide is available as a free download through our website Step 1 Acquire a reasonably bright guide star and begin guiding in RA only turn off Dec guiding note X and Y are switched on the Maxim parameter page as of v3 07 Use a 1 second or faster refresh rate so you can see the motion of the guide star as you begin to move it around Magnify the screen to 1600x and place the cursor in the middle as shown Check to make sure that the mount is guiding adequately in RA and that the guide star is not bouncing around due to poor seeing Best results will be achieved when the RA guiding is 0 5 pixels average in RA 7 gpa pm o m Step 2 Put the keypad button rate at 0 5x Press the keypad North button until the guide star has moved approximately 6 pixels from the center Now press the South button in very short pulses and note which direction the star moves It should move back toward the middle after a few button presses It might move slightly up or down or it might continue to move further away from the middle or any combination Please note exactly how far and in which direction the guide star moves pixel position is displayed in the guide
36. ELS control boxes became quite warm but never hot We do not recommend this high a voltage as a general practice We cannot be sure of the long term effects of such a high voltage on the electronics over time There is also simply no reason for such high voltage since the system performs so well at the recommended voltages 35 SERVO MOTOR DRIVE THE BRAINS OF YOUR MOUNT GTO Control Box Model GTOCP3 The GTO control box contains all of the circuitry to drive the two pairs of servo motors and the logic required to navigate the sky It will be operational and track at the sidereal rate when connected to both motor gearboxes of the mount and a power source In order to control the movement of the mount you will need to connect at least one of these e GTO Keypad e PC computer with PulseGuide by Sirius Imaging The CD with this program is included with the mount The CD includes a complete user s manual in PDF format For the most updated version of the software check out the Web site www pulseguide com Please refer to the section later in this manual for further information regarding the capabilities of this program e Computer with a planetarium program or observatory control software Astro Physics now has a fully supported ASCOM V2 Driver available A more detailed listing of software is in the Controlling Your GTO Mount section later in this manual In addition see the website s ASCOM page for details on the ASCOM
37. Planewave 7 652 n DOVEPW dovetail on AP 1200 and 3600GTO PASES n 6 3 8 16x1 SHCS DOVE3622 22 Dovetail Saddle Plate for 3600GTO 4 3 8 16x1 1 2 SHCS SB3622 oR Dovetail Sliding Bar for DOVE3622 2 3 8 16x1 2 low profile SHCS SB3627 4 1 4 20x7 8 SHCS for lock down DOVELM2 may also be attached to 900 mount with 1 1 4 20x5 8 FHSCS and 1 1 4 20x3 4 SHCS 11 30 2010 49 22 DOVETAIL SLIDING BAR DRAWING SB3622 for attaching to the 3600GTO Dovetail Saddle Plate DOVE3622 5 16 thru holes with crosswise spacing at 4 500 for largest AP rings i e for Riccardi Honders Lengthwise spacing interval is 2 00 1 4 20 tapped auxiliary Note the DOVEPW can NOT be used in the holes for various acces side by side configuration with this plate sory attachment 7 450 CO OOO oboo OOO 00 000V olo0 0002 O O O O aO0O0 00 Ce 00S 000 000 0 4 500 _ a 5500 350 C O ol O o O 10 O o O o IDO lo O o O O O ol O 10 O DOI 3200 O O eg O O O O O O O O OOO W200 C0200 C000 A200 OOO AOdO0 c 2 oOo ff og O O o O Q 1 4 20 tapped holes with 8 220 crosswise 1 4 thru holes with 3 200 spacing used for locking SB3622 to the crosswise spacing for AP rings DOVE3622 for extra rigidty and security Lengthwise spacing interval is Lengthwise spacing interval is 1 000 2 00 Ob 0S seb O71 one N ooo Vooo ooo ooo Yooo Yooo ooo Lene ne 000 000 000 000 0 00 000 000 000 aa T aa OOO O00
38. Pro curve from our extensive testing is then pre programmed into the servo Maximum slew speed 2 5 degrees second 600x sidereal PRECISION ENCODER AND LIMIT SWITCH SYSTEMS OPTIONAL Encoder Details Ultra precise Renishaw stainless steel 9 encoder ring with nanometer scale pickup Encoder Corrections Periodic as well as non periodic error reduced to below 1 2 arc second Encoder Control GTOELS Control Box provides complete encoder control and servo drive interface Motor reduction gear train Power consumption Periodic Error native error prior to any error correction Home Limit Switches Adjustable switches can be used with simple wiring or software optional GTOELS Optional Software Control for GTOELS box included with Precision Encoder System allows flexibility for having Home Limit Switch System both active limits and the ability to track past the meridian Advanced home functions INTRODUCTION The 3600GTO German equatorial was designed to meet the needs of the advanced observer who requires a mount with maximum strength and rigidity for today s large imaging instruments The excess material in both axes has been carved out while retaining a heavily ribbed structure for internal strength and rigidity The axes can be separated for transport to a remote dark site but this mount is primarily intended as an observatory platform for large loads and critical applications The DC servo motor drive with GTO computer s
39. Revised GTO Quick Star Drift Method of Polar Alignment also in the Keypad Manual This will get your alignment extremely close 24 Attach Counterweight Shaft and Counterweights IMPORTANT e Always attach the counterweights before mounting the telescope _ 4 N to the cradle plate to prevent sudden movement of an unbalanced 4 tube assembly which may cause damage or injury e Remember counterweights are heavy and will hurt if they fall on your foot 1 Thread the counterweight shaft onto the Dec axis The counter weight shaft for the 3600GTO is large and heavy and can be quite unwieldy Be careful not to cross thread This may be another job best done by two people Having done this now a few times solo have found the best way is to use my left hand up near the threads and my right hand on the end of the shaft I am right handed The left hand guides and stabilizes while the right hand supports and turns the shaft Turn the shaft at least three full rounds into the adapter before relaxing your support on the bottom of the shaft Do not tighten too much since you may need to remove it later 2 Remove the safety stop from the end of the counterweight shaft Add sufficient counterweights 30 Ib counterweights are available to the shaft to balance the telescope you intend to use Most configurations will require between 80 and 100 of the total instrument weight including plates rings cameras etc Loosen the counter
40. ains software with which we have at least a little familiarity e The Sky and Bisque Observatory Software Suite families of products from Software Bisque These include The Sky 6 Professional Edition Windows The Sky X Windows and Mac versions TPoint Windows and Mac Versions CCDSoft jointly developed with SBIG Windows Orchestrate and other components in the Bisque Observatory Software Suite The Bisque brothers have written their own native Astro Physics drivers and their Windows programs also can use the ASCOM interface e Starry Night Pro Plus from Simulation Curriculum Corp Windows version with ASCOM support and Mac version with native driver e The Earth Centered Universe ECU v 3 1 or later from Nova Astronomics Windows As of Feb 2010 the latest version was v 5 0 Versions including 4 0 and later have full client support for ASCOM telescope drivers including the Astro Physics V2 ASCOM driver e Chris Marriott s SkyMap Pro Windows Native drivers for the Astro Physics GTO System have been included since v 7 Starting with v 10 ASCOM support was added as well e Equinox from Microprojects Astronomy Software Darryl Robertson Mac e Voyager from Carina Software Windows and Mac This product does not use the ASCOM interface e ACP Observatory Control Software by DC 3 Dreams Robert B Denny Windows ACP uses the ASCOM interface e MaximDL from Diffraction Limited Windows
41. ase in wattage is mostly wasted energy that is dissipated as heat by the voltage regulators This heat if allowed to build up to excessive levels can be harmful to the electronics The tests above were performed under ideal conditions You should expect slightly higher demands under real world observatory conditions Most important among the variables that will affect your mount s power requirements are the degree of system balance the ambient temperature and above all the perfection of the worm mesh We consider 14 to 18 volts at 10 amps to be ideal for virtually all situations Voltages of 20 or slightly higher should ONLY 33 be considered in extremely cold conditions We do NOT recommend EVER exceeding a typical 24 volt system The information on higher voltages is provided with considerable reservation with the understanding that customers who do not have U S standard 110 to 120 volt 60 Hz AC current may have difficulties finding a power supply similar to our PS15V10AC It should by no means be considered a license to apply excessive power to the mount Please remember there is current loss and voltage drop at every connection and in every inch of wire through which the current must travel This is why we strongly advise against using any kind of extension cord between the mount s power cord and the DC power source you are using It is why we chose a very fine strand low resistance cable for the power cord and limit its length to 8 feet
42. ately related Note Please pay particular attention to the section that follows on cable management before actually attaching any instrument mounting plate to the 3600GTO In terms of actual work flow you will almost certainly need to install your cabling before attaching the plate However you also need to understand how the plates attach in order to best plan your cable routing 3600GTO Declination Hub Mounting Surface Objective End Both Hemispheres 4 side by side Mounted Instruments Astro Physics offers several options for attaching a AIDAS wide variety of instruments to your 3600GTO These i f options will be detailed below Alternatively you may fe 3 a have a custom plate machined by your favorite machine shop for your particular instrument The declination hub hole pattern is shown at the right Objective End Objective End Southern p ve Northern Hemisphere Indi ator mark a Indicatormark Hemisphere fon axis hub on axis hub a ical AMIS oT T Astro Physics 22 Dovetail System Focus End Sea etal Focus End Northern Southern 22 Dovetail System Overview A special 22 Hemisphere o 2 ee Hemisphere Dovetail Saddle Plate DOVE3622 has been 4 Pi A designed for the 3600GTO There are two Dovetail Sa a i A o 8 Sliding Bars a 22 bar SB3622 and a 27 bar Screw pth amp S0 equally 2 A ge SB3627 designed specifically for the 22 Dovetail f SEE Clutch k Sa Saddle
43. ations If the LED turns yellow and you are providing adequate power this means that your motors are overloaded probably due to an unbalanced load on your mount Refer to the section on balancing and the troubleshooting section of the manual for the solution KEYPAD Receptacle Attach the 5 pin male connector plug of the keypad receptacle and lock in place on the receptacle push in the knurled ring then turn RS 232 Ports 2 These serial ports are used to connect your mount to your external computer We provide one 15 ft serial cable CABSER15 with your mount You may provide your own additional straight through non crossing cables with a 9 pin DE 9 male connector to interface with the GTO panel or you can purchase them directly from us and be assured that they are the correct type of cable We have provided the locking posts to secure the cable firmly onto the control box If your serial cable does not have a 9 pin connector you can use a gender changer or adapter to convert it 37 Please note the use of crossing reversing null or null modem GTO Control Box cables is a frequent source of failure and frustration Make sure that your Serial RS 232 Ports serial cable is wired straight through DE 9 Female Jack When you are controlling the position of the mount with a computer program en such as PulseGuide Software Bisque s TheSky or Simulation Curriculum 286 06 Corp s Starry Night
44. ator cable for a plug in type guiding eyepiece with an illuminated reticle available from several manufacturers insert the 3 5 mm mono phono plug into this jack for power Reticle brightness can be adjusted with the keypad PulseGuide or the AP V2 ASCOM Driver Refer to the section pertaining to reticle illuminator adjustment in the GTO Keypad Manual for further information 38 AUTOGUIDER Port Receptacle This receptacle interfaces with the RJ 11 6 modular plug of an autoguider GTOCP3 AutoGuider Port cable purchased separately or as part of a CCD Imaging Camera or RJ 11 6 Receptacle Autoguider The autoguider will be functional and ready to go as soon as you Pin 1 NC plug it in Please refer to the appropriate manual from the manufacturer for 2 GND operation of the autoguider 3 East Pin Positions 4 North Jack 623k 5 South LULL 6 West 6V Auxiliary Jack This 6 volt output accepts 3 5 mm mono phone plugs It s original purpose was to power the Pentax 6x7 camera directly from the mount Its most common usage today is to power the StarGPS It has also been used to power BlueTooth units for wireless connection to the mounts COM ports Center is positive It will supply up to 200mA of current Be sure of your device s power requirements and polarity before attaching N and S Switch Select northern N or southern S hemisphere as needed When you slide the switch to the opposite position the tracking direction of the drive
45. ble port cover plates where cables can then exit the mount for routing to your power supplies computer etc Note that at least one of the Cable Port Cover Plates is blank It has no connectors For your accessory items you can remove the blank Cable Port Cover Plate s and allow your cables to exit the opening Or for a cleaner appearance you can modify your blank Cable Port Cover Plate to attach receptacles just as we have done on the Servo Panel Yet another option is to cut a slot or slots into the blank Cable Port Cover Plate The slots would only need to accommodate the cable thicknesses and would not have to be large enough to pass the plugs on the cable ends Specific Instructions for Routing Your Auxiliary Cables What follows are some more detailed instructions for installing your cable package into the 3600GTO You will of course have to tailor the instructions for your own particular needs These instructions are for the routing of auxiliary cables for cameras dew heaters focusers and other devices that are not a component of the 3600GTO The mount s own cables are discussed earlier in this manual in the sections on mounting the declination axis or in separate documentation for the Limit Homing Switch 36LSS and Precision Encoder Systems on the 3600GTOPE Use the Assembly Diagram found earlier in the manual to help identify the named parts below 1 Start with the assembled mount on your pier At this point you do not need th
46. box at right in Maxim Please allow a moment for the star to settle down after each button press Step 3 Press the South keypad button until the star has moved 6 pixels off the center in the canal Sarge Samed Peal rasa See freee OPPOSite direction Repeat Step 2 and note i pe es exactly the motion of the guide star as you r Erma Ess move it with the pulsed motion at 0 5x t eral REEE CER You may wish to enable Track Log to record the numbers for further study Please note on the log what you did at what time so the results will be useful later You have now characterized the Dec axis 09 15 03 48 ASTRO PHYSICS MOUNTING PLATE FASTENER CHART A P Part Description Ships with 15 Flat Plate FP1800 1 4 20x1 2 SHCS for mounting to 400 M6 1 0x16mm FHSCS for mounting to 600E 8 Dovetail Plate 1 4 20x5 8 SHCS for mounting to 900 or Mach1GTO requires Q4047 or to attach to SBD13SS or SBD16SS DOVE08 1 4 20x1 2 FHSCS for mounting to 400 or MachiGTO M6 1 0x16mm FHSCS for mounting to 600E 1 4 20x5 8 FHSCS for mouting to 900 or 1200 10 32x3 4 SHCS for mounting as Accessory Plate onto A P rings 1 4 20x5 8 SHCS for mounting 400 or Mach1GTO M6 1 0x20mm SHCS for mounting 600E 8 5 Dovetail Plate for Losmandy D Series Plate 1 4 20x5 8 FHSCS for mounting to 1200 1 4 20x3 4 SHCS for mounting to 900 or 1200 or to attach to SBD13SS or SBD16SS 16 Dovetail Plate for Losman
47. chance we will post a complete set of pictures on our web site showing how to check for this loose gear condition Meanwhile you can take the cover off the motor gearbox and acquaint yourself with the spur gears inside Do 46 not be afraid to move and wiggle things by hand to see how stuff works One more thing sometimes a person will be absolutely certain that it is the Dec axis that is giving him a problem because the CCD program he is using shows some improper function in the Y axis and he is absolutely certain that Y Dec After much sending of equipment back and forth to our facility it finally is determined that it was the other axis after all that had the problem PLEASE please make sure that you have identified the proper axis In the case of any kind of motion problem like this it would be really helpful if you removed your camera inserted an eyepiece with crosshairs and actually looked to see what was happening You can then identify exactly which direction R A or Dec is moving after a slew Sometimes because of mix ups in the CCD software Maxim for instance the axes are identified backwards When you are trouble shooting remember R A is the only axis that must move at the sidereal rate and is the only axis that can trail a star if it is not moving correctly at that rate The Dec axis does not move after a slew and will not trail a star except by a very slow long period drift due to polar misalignment etc It will not tra
48. crews loosened The clutches in the 3600GTO are of a different design than those found in the 900 and 1200 series of mounts The set screws have spring loaded tips so you may think they are loose when they are actually still applying pressure The set screws must be backed out between 3 8 and 1 2 to fully disengage the clutches see the section earlier in the manual Even fully disengaged the clutch action is stiffer than the almost frictionless action of the 900 and 1200 mounts The LED on the GTO Control Box changes from red to yellow and the motors stop or go out completely 1 The motors are overloaded probably due to an unbalanced load on your mount Rebalance your telescope and then press one of the N S E W buttons to reset the keypad Re enter the last object on your keypad and the scope will slew to the correct position Even though your motors had stopped the logic in the control box retained the scope position in memory As long as you didn t change the pointing position of the scope you are still calibrated If the scope was moved during re balancing simply enter a nearby bright star on the hand controller press GOTO and allow the mount to finish slewing You can then move the scope manually or with the N S E W buttons to center the star in the eyepiece and press the 9 RECAL button This will recalibrate the mount Additional explanation The GTO drive circuit includes logic for overload protection to prevent burning out the
49. d Numerous other software solutions are also available Star Drift method Traditionally this very time consuming procedure has been regarded as the most accurate method of polar alignment However if you are using the old method of drift alignment star near eastern horizon etc you are doomed to failure To obtain more accurate results choose stars somewhere near the celestial equator due south or slightly east and west but not below 45 degrees elevation If you attempt to drift align below that you will encounter atmospheric refraction which skews your alignment Helpful Advice Members of the ap gto Yahoo group occasionally discuss alternative methods of polar alignment that they have found helpful We suggest that you participate in this Internet discussion group Follow the links from the sidebar of our Web site to find the group 31 POWER CONSIDERATIONS Introduction The Astro Physics Servo Drive System uses industrial components and our circuit boards are built with aircraft quality assembly techniques We chose a sturdy industrial handheld computer as our keypad These components are far more rugged than conventional consumer electronics and they will continue to function properly well below zero degrees F 18 C The keypad uses a vacuum fluorescent display that does not lose its speed or readability in the coldest winter conditions all the way down to 40 degrees F 40 C However if you plan to use your mount in ex
50. d as a cabling port See additional details in the este eeeeeee seseo next section under Cable Management As mentioned above you can also use two or even three depending on instrument size 16 Dovetail Saddle Plates DOVELM162 introduced in February 2009 in a side by side configuration for multiple instruments These plates are drilled to attach directly onto the SB3622 and SB3627 although they attach in a different manner You can also use the 16 5 Dovetail Plate for PlaaneWave DOVEPW in side by side SB3627 with DOVEPW and DOVELM162 configurations See details below in side by side configuration 1 4 20x5 8 Socket Head Cap Screws 4 Bottom View e The DOVELM162 can be mounted either centered or offset to the front or back to help with the tricky job of balancing multiple instrument setups See photos at right o The DOVELM162 accepts the industry standard Losmandy D series plates or any other plate manufactured to the Losmandy D dovetail specification o The DOVELM162 also features lock down knobs that can be firmly tightened with an DOVEPW attaches with four 5 16 18 Allen wrench x 3 4 socket cap screws from j n underneath the SB3627 _ e The DOVEPW also has three mounting positions to aid in achieving the front back balance DOVELM162 attaches with 1 4 20 x 1 socket cap screws and possibly one 1 4 20 x 3 4 flat head socket cap screw for maximum offset as sh
51. de between 35 and 40 degrees or close to that anyway you might also consider performing your rough alignment before actually mounting the declination axis onto the R A axis At higher or lower latitudes there is no point in setting the rough altitude until after the declination is safely mounted See the section on rough alignment later in the Final Mount Assembly section Inclinometer 10 2 Prepare Mating Surface for Declination Axis The carved out face of the R A axis declination mating surface shows three indentations for the clutches One of these is centered between two of the attach ment bolt holes while the other two are each off center of a single attachment hole You will also note that there are two small indicator i A grooves or indentations on opposite sides of the mating face and a third y Ww small groove on the outside of the mating hub just below the clutch that M 1 Clutches s N is centered between the two bolt holes Orient the mating surface of the R A axis as shown in the photo at right The mount will have been shipped already in this position Be sure to re tighten the clutches before installing the Dec axis See the section on clutches later in the manual 3 Make the Cables Accessible The mount is shipped and may be transported with the Y cable attached to the R A motor gearbox and the R A cable access plate on the rear of the R A axis The declina tio
52. ding points for each adjustment more the case Knob Graduations Sight Window during fine adjustment later This will allow you to Azimuth Adjuster Block exactly undo any adjustments that are made in the wrong direction Do not leave the knob you have backed off loose It must be gently but firmly snugged against the azimuth adjuster block to hold the azimuth angle you have set One full turn of the Azimuth Knob is approximately 0 38 degrees 22 9 arc minutes Small graduations are 55 arc seconds long graduations are 4 6 arc minutes If you have accurately marked a plumb line due north from your pier on your observatory wall you will perform the rough azimuth adjustment first Adjust the altitude low enough that you can see the plumb line through the polar alignment sight hole If using a compass align the compass along either side edge of the large square mount base 22 The Altitude Latitude Adjuster The mount s polar axis is held in place between the two side plates of the Polar Axis Lock down Polar Fork The axis pivots on two Center Pivot Bolt Assemblies one on Bolts Loosen each side plate that include two bearings each one on the inside and the other on the outside of the respective side plate 4 bearings total Because of these bearing assemblies the Center Pivot Bolts should never be loosened On either side of each Center Pivot Bolt are two Polar Axis Lock down Bolts that take a 5 16 hex wrench from the included
53. driver PLEASE NOTE Because the 3600GTO uses different gearing than our other mounts the GTOCP3 control boxes are NOT interchangeable as they are between for example a 1200GTO and Mach1GTO DO NOT use a GTOCPx control box from another mount on your 3600GTO and DO NOT use the 3600GTO s GTOCP3 on any other mount unless you have TWO 3600GTOs The GTO Servo Control Box is mounted directly onto the side plate of the 3600GTO mount as described earlier Please remember that this box contains advanced electronics and must be treated with the same care given to other fine equipment You can see that the unit is machined of aluminum and is built to be rugged however it is not indestructible ASTRO PHYSICS INC GTO CONTROL PANEL a 3 MOTORS lt v 5 w 3 zZ w Q S AUTOGUIDER Ka KEYPAD f RETICLE 12V S MODEL GTOCP3 Pre loaded PEMPro Curve Your mount was tested at our production facility with a special version of PEMPro Periodic Error Management Software After ensuring that the mount s uncorrected periodic error is within our specifications of 5 arc seconds peak to peak we generate a unique optimized PE curve for your specific mount and then save the corresponding PE correction curve to the GTOCP3 control box for you to use By turning PE on from the keypad PulseGuide or through a client program with the Astro Physics V2 ASCOM Driver you can take advantage of this PE curve the very first tim
54. duct That being said we suggest that all 3600GTO owners adopt this manual for regular guidance with their mounts The benefits of the improved information should easily outweigh the minor differences between mounts from earlier production runs and the current one There will be a few things like the re designed cable covers that owners of mounts from the first production run will not have In a similar fashion owners of brand new mounts should be aware that some of the photos that were used in this manual are of mounts from the first production run You may therefore see some slight differences whether you have a brand new mount or an earlier mount but none of these were deemed to be of significance As always we highly recommend the Technical Support Section of our Web site for the latest information and for future updated versions of this manual Older versions are also available there PLEASE RECORD THE FOLLOWING INFORMATION FOR FUTURE REFERENCE Mount Serial Number Keypad Serial Number GTOCP3 Serial Number GTOELS Serial Number Purchase Date MODEL 3600GTO PARTS LIST MODEL GTOCP3 Polar axis assembly right ascension R A with Integrated Precision Adjust Rotating Pier Adapter Azimuth Adjuster Assembly with two 1 4 20x1 3 4 socket cap screws for mounting Servo Control Box GTOCP3 Declination Dec axis assembly with two 3 8 16x1 and four 3 8 16x1 1 2 socket head cap screws for attachment 31 5 30 0
55. dy D Series Plate for 6 1 4 20x1 SHCS for mounting to 900 or 1200 DOVELM16 S 1200GTO S version for 900 or MachiGTO 4 1 4 20x7 8 SHCS for Mach1GTO 6 1 4 20x1 SHCS for mounting to 900 1200 or MachiGTO uses 4 or to attach to SBD13SS or SBD16SS 1 1 4 20x3 4 FHSCS opt 900 or 1200 for end positions 4 1 4 20x3 4 SHCS for SB3622 in side by side configuration and for attachment to blocks for ring top mounting ies 1 4 20x1 FHSCS for mounting to 900 Belge env rare Gre ean a 1 4 20x1 1 4 FHSCS for mounting Mach1GTO 1200RP15 15 Ribbed Plate for 1200 6 1 4 20x3 4 SHCS for mouting to 1200 200RP 24 Ribbed Plate for 1200 6 DOVE15 15 Dovetail Plate DOVELM2 A oO 16 Dovetail Plate for Losmandy D Series Plate for 900 1200 Mach1GTO Also for 3600GTO w DOVELM162 SB3622 or SB3627 Can also be mounted on AP ring tops with blocks 1 4 20x1 SHCS for mounting to 1200 1 4 20x5 8 FHSCS for mounting to 900 1 4 20x1 FHSCS for mounting to MachiGTO 1 4 20X1 2 SHCS 900 Mach1GTO Adapter for use with DOVE08 Te V D O A A N v Acorn Nuts 1 4 20 Nuts 1 4 20x3 8 SHCS 10 32x5 8 FHSCS 10 32 Nut 1 4 20x1 low profile SHCS for attaching the SBDAPB or LMAPBLOCKS 1 4 20x1 1 4 FHCS for attaching directly to AP Rings 1 4 20x1 2 low profile SHCS 1 4 20x3 8 SHCS 2 for Stowaway 1 for Safety Stop 1 4 20x7 8 SHCS Stowaway with SB0550 as spacer 1 4 20x3 4
56. e although at this point you are not yet ready to perform it The daytime routine requires having an instrument mounted on your 3600GTO but that instrument can be quite small and light in weight for convenience To use this method first read through the rest of the mount assembly instructions Once you have read and understand those instructions you can go ahead and attach a mounting plate with a small instrument and probably no more than the counterweight shaft without weights to perform the daytime routine We recommend the daytime routine as the best first step in the fine alignment process You might even want to consider the following as a method to get yourself to the almost perfect state of alignment before mounting up your full and very heavy instrument setup and counterweights This is presented here as an outline Details are in the appropriate sections later in this manual and in the keypad manual 1 Attach the Counterweight Shaft and then attach your mounting plate and a finder scope or a small wide field telescope in adjustable guidescope rings Depending on the small scope you use you may need to add a bit of weight to the mounting plate to balance out the 3600GTO s rather heavy counterweight shaft 2 Use the daytime routine as described in the keypad manual You can use the edge of the mounting plate for your bubble level if the level is too long for the scope 3 Once aligned with the daytime routine proceed to the
57. e Azimuth Adjuster Block 3 Mark your starting position on the knob that you plan to back off not the knob that will be pushing the mount using the knob s graduation marks A tiny piece of blue masking tape cut into a mini pointer works really well for this The tape pointer is also a great trick for fine focus adjustment when imaging 4 Back off the knob you have marked by just a few graduation marks or however many you believe will bring you to alignment See the scale information below 5 Turn the adjusting knob so that it turns the mount until it tightens the azimuth block against the knob you backed off in step 4 At this point no further shifting of the azimuth is possible and the mount is locked in its new azimuth angle 6 Check your alignment If you went the wrong way you will Know how to get back to the exact spot where you started because you marked your starting point If you need to go further you can repeat this procedure using ever smaller increments until it is perfect You can also move the blue tape pointer to each new starting position 7 Make your next adjustment the same way taking ever smaller steps The small graduations are 55 arc seconds per graduation long graduations are 4 6 arc minutes per graduation one full turn is 22 9 arc minutes or 38 deg Altitude Adjustment As mentioned earlier the mount s polar axis is held in place between the two side plates of the Mount Base Polar Fork Assembl
58. e counterweight shaft installed The DOVE3622 Dovetail Saddle Plate should not be attached yet The 22 Servo Extension Cable CABGTOR22 and the external cables for the Limit Homing Switch CAB36LS or your own custom cable and Precision Encoder Systems CAB36PE should also be disconnected from the receptacles on the R A Rear Cover Plate Panels for this operation 2 Lower the altitude of the R A axis using the Altitude Adjuster Hand Wheel as discussed earlier in the manual to provide easy access to the R A Rear Cover Plate and its panels Clockwise lowers the altitude 3 Remove the Auxiliary Panel the blank panel at the bottom from the R A Rear Cover Plate Your added cables will eventually feed through this opening 4 Remove the R A Rear Cover Plate by removing the six 1 4 20x3 4 socket cap screws around its perimeter with the 3 16 hex wrench from the set This will allow you to feed the additional cables through the axis more freely Be careful to handle the R A Rear Cover Plate gently as it will be dangling from the attached wires 5 Feed your cables through the mount starting at the opening through the Dec axis Help each cable end or bundle around the corner and into the right ascension axis 6 Feed the cables out the rear of the right ascension axis and then through the opening provided by the Auxiliary Panel 7 Adjust the cable length that is hanging out of the declination axis There should be absolutely no ten
59. e hole pattern for the mount s Pier Adapter Plate is oriented as shown in the preceding diagrams and the photo at right with side mounting holes at each of the four compass points j 2 Set the R A Axis in place Carefully set the 3600GTO right ascension axis polar fork assembly p into the 3600 Flat Surface Adapter 3600FSA or into the open top of your pier Itis ideal to have three people involved in this operation two people lifting the assembly by its square base one from each side and the third person guiding the Pier Use Azimuth Adjuster Adapter Plate into the 3600FSA or the top of the pier to line up holes betweet P Depending on the configuration of your observatory Pi 14 ier Adapter and Flat you may also wish to employ a hoist or other lifting rface Adapter 360 D g d device A strap can be easily run through the axis to facilitate a mechanical lifting device 3 Line up the Pier Adapter Ifthe side thru holes in the pier or 3600FSA are not perfectly lined up with the tapped holes in the mount s Pier Adapter Plate line them up by grabbing hold of the Azimuth Adjuster Block on the bottom rear of the mount and using it to turn the Pier Adapter Base Do not try to line up the holes by turning the large square base of the mount Since this is a Rotating Pier Adapter simply turning the base without the Azimuth Adjuster in place will turn the top plate with out also turning the part of the plate that
60. e holes are lined up The small groove on the outside of the RA mating hub should be in line with the CW shaft if you have everything oriented correctly When everything is lined up insert the shorter 3 8 16 x 1 Socket Cap Screws in the center attachment holes on each side and start each bolt in a couple turns Attach the four longer 3 8 16 x 1 1 2 Socket Cap Screws in the outside attachment holes on each side of the Dec axis Lightly snug all six bolts Then tighten the center bolt on each side and lastly tighten the four outside bolts 12 4 Retrieve and Attach the Declination Servo Cable Remove the Dec axis servo cable plate from the axis body center photo using a 7 64 hex wrench Once the plate is removed reach into the declination axis to retrieve the Declination Servo Cable from the inside of the R A axis You may need a step stool or small step ladder to do this In our experience we have found it easiest to first pull the cable out through the declination hub so that you can be sure that nothing is tangled Next you simply get a good grip on the plug and plunge your hand back into the declination hub to feed the plug out through the cable port in the declination axis Once the cable is secured to the servo connector the cable plate can be replaced by carefully positioning the cables in the appropriate slots provided in the cover Do not overtighten these bolts and risk damaging the threads We recommend that you tigh
61. e you use your mount This PE curve should remain valid for several months as your gears run in and will probably suffice for many mount owners J 19 Instructions for turning the PEM on in the keypad s Tools menu are found in the keypad manual The full version of PEMPro v 2 x has been included with your 3600GTO so you can actually produce an even more refined periodic error curve by using more worm cycles than we can do here at the factory Although we can make no promises we have heard numerous reports of sub arc second periodic error from experienced users running 6 or more worm cycles in PEMPro It is suggested that you save the existing curve to your computer before overwriting it in the control box with a new curve just in case you do something wrong in your first attempt ata PEMPro run That way you can re load the old data back to your control box if needed 36 Lead Free RoHS compliant Electronics Starting in 2006 we began phasing in lead free electronics for all of our mounts In the first phase all GTO mounts and other electronics shipped to customers in the European Union were built with lead free electronic components due to ROHS regulations that went into effect on July 1 2006 As of mid 2007 all of our electronics adhere to this safer and more environmentally responsible standard All functions and capabilities of the Servo System were maintained with the lead free components All 3600GTO mount
62. eciable loss of download speed As with any computer electronics change is the only real constant Please check our Web site for the latest information on products for computer connectivity More distantly remote observatories will generally require a computer or I P addressable server in the remote observatory itself and a high speed internet connection for communication with your home computer Such solutions are beyond the scope of Astro Physics to supply or support For a more detailed discussion go to our Web site www astro physics com We also recommend that you go to the Yahoo ap gto user s group access it through our Web site and type serial usb or pcmcia into the search box Also be sure to keep an eye on the What s New pages of the Web site for further developments in this area FOCUSER Jack If you have a motorized focuser with a DC synchronous motor like the JMI Motofocus you can attach the 3 5 mm mono phono plug connector here This connector can NOT be used with motorized focusers that use stepper motors as they require their own separate drivers Refer to the section regarding focus adjustment in the GTO Keypad Manual for instructions on using the keypad controller to adjust focus Note Low focus speed voltage is approximately 1 7 volts and high focus speed voltage is the straight through voltage of your power supply RETICLE Jack 1 6 to 4 6 volt variable output If you wish to use the illumin
63. ehind the Azimuth Adjuster Block Be sure to start all seven cap screws with their washers before tightening any of them Then snug all seven cap screws down before finally tightening them all securely Set the R A altitude latitude higher Your R A axis will have been shipped and should be transported in a low but not quite bottomed out latitude position of about 18 degrees At this point in the assembly process you will want to raise the altitude adjustment to around 35 to 40 degrees even if you are at a lower latitude This will provide an angle for the declination axis to be in a relatively balanced state when it is set in place on the R A axis It will be much easier to align the bolt holes and secure the two axes together if you arent also holding the 84 Ib Dec axis in place against gravity Loosen F To raise the altitude angle first loosen the forward and the rear polar axis lock down bolts in the curved slots on the sides of the polar forks as shown at right Do not loosen the larger center polar axis pivot bolt The Hand Wheel s crank handle will be in the folded position To unfold the handle for altitude adjustment pull up on the handle and then simply fold it out as shown in the photo Turn the Altitude Adjustment Hand Wheel counter clockwise to raise the angle of the R A axis to around 35 or 40 degrees You may find an inclinometer handy as shown below If you are setting up your mount at a latitu
64. ern as you would a car wheel and finally tighten DOVE3622 them all down Please note that the two outer positions marked C and B will use 8 attachment bolts while the center position marked A can use all 10 available mounting holes 8 bolts are more than enough for the full load that the 3600GTO can carry 15 When mounting the DOVE3622 on your 3600GTO the Cable Channels shown in the photo above should be on the eyepiece or camera end of the plate See the next section on cable management The 22 and 27 Sliding Bars SB3622 and SB3627 These sliding bars were designed with versatility and flexibility in mind The robust male dovetail plate pictured at right features a myriad of holes throughout the entire length that can accommodate a variety of instrument configurations at various balance points such as any mounting rings that have the Astro Physics hole spacings of 3 2 and 4 5 We also offer hole spacings of 3 5 5 5 and 7 45 from one end of the plate to the other The two plates offer somewhat different arrangements of the holes for attaching various rings and additional plates Additional information can be found in the detailed drawings at the end of the manual Both plates will accept the 16 Easy Balance Dovetail Saddle Plate for the D Series Style Plate DOVELM162 in side by side arrangements SB3622 g 3 2 AP S pacing for 1 4 bolts 3 5 f SETT a for 1 4 bo
65. es a problem guiding in R A can be the result of a Dec axis mechanical problem Not knowing this you will be forever chasing down the problem on the R A axis and never reaching a solution Characterizing your Dec Axis will at least show you that the mount reacts properly to the 4 guide directions If it shows a problem area then at least we will know how to fix it Once you know that the mount is tracking in a normal fashion with normal periodic error profile you can go from there to begin setting up your guiding parameters It is not a piece of cake to get a guider like the ST4 to work flawlessly It is an art but once you know that the mount responds properly to the guide inputs it should be possible to set it up to work accurately If any problems occur please don t hesitate to contact Astro Physics for assistance We may add additional troubleshooting tips to future versions of this manual or in a separate technical document so we encourage you to check the Technical Support section of our Web site We also strongly recommend that you participate in the ap gto discussion group at yahoogroups com In addition to the huge knowledge base of the various members the technical support staff at Astro Physics also participates to help solve problems and answer questions ASTRO PHYSICS INC 11250 Forest Hills Road Machesney Park IL 61115 Telephone 815 282 1513 Fax 815 282 9847 support astro physics com www astro physics com 4
66. f PulseGuide by Sirius lmaging PulseGuide is a stand alone Windows 98 ME 2000 NT4 XP Vista Windows 7 utility that provides complete remote control of all Astro Physics GTO mounts It derives its name from its most distinctive feature pulse guiding which can improve unguided tracking Specifically it can help correct tracking errors caused by polar misalignment and atmospheric refraction You can also train PulseGuide to track objects moving relative to the stars such as asteroids comets and the moon In addition to pulse guiding PulseGuide also has many useful utility features PulseGuide was written by Ray Gralak of Sirius Imaging The complete PulseGuide user s manual is included on your PulseGuide CD in PDF format Please read it carefully to take full advantage of this powerful mount control software See www pulseguide com for the latest information See ojx The Astro Physics ASCOM V2 Driver Astro Physics began the development of a company supported ASCOM V2 driver in 2009 Please see the Astro Physics Web site for current information on the ASCOM driver http www astro physics com products accessories software ascom ascom htm This driver provides full mount control for all of the Astro Physics GTO mounts It has been developed with remote operation in mind and its functions were designed to be highly robust It features a very user friendly graphical user interface GUI This V2 driver requires ve
67. his manual entitled Slewing Your Mount in Below Freezing Temperatures The declination axis does not appear to be moving properly How can I check it Please refer to the appendix for the instruction sheet Characterizing the Dec Axis Motions which explains how to use Diffraction Limited s Maxim DL software to characterize your mount s performance When press the E button on my keypad it takes forever for the star to finally stop Adjusting the back lash control using the keypad helped but the problem is still there First the problem is most often caused by the worm and worm wheel not being in mesh this is often the case when a used mount is purchased and the previous owner never ever adjusted the worm mesh or the mesh was altered during shipment When the worm is out of mesh it takes the motor many seconds to reverse the tooth contact from leading to trailing edge because it is running at the very slow sidereal rate One could simply dial in an appropriate amount of R A backlash into the keypad in order to compensate for this R A backlash compensation simply kicks the motor momentarily in the opposite direction at high speed until the opposite teeth have made contact and sidereal tracking can take place The ideal solution is to adjust the worm backlash so that this delay does not occur Please refer to the detailed information in the technical support section of our Web site If the information is not there please contact Astro
68. his mount wherever you operate it Therefore we also want you to understand the mount s power requirements from the outset so that you can provide the best power source possible to the system If you have purchased our recommended 15 Volt 10 Amp Power Supply PS15V10AC to power the mount just the mount and nothing else you will be fine and can probably skim through the following text with few concerns If you plan on using other power sources please read carefully and try to follow the guidelines presented below We end this introduction by presenting the following table This table takes the necessarily limited information from the Specifications Page at the beginning of the manual and expands it to provide a better understanding of the 3600GTO s power consumption In the table ELS refers to the optional combined Precision Encoder System Limit Switch System and the GTOELS Secondary Control Box All results include the GTO Keypad 3600GTO Power CoNnsumpPTION TABLE BoTtH AXES SLEWING AT SIDEREAL TRACKING 600x Mount PARAMETERS Watts Larger loads imbalance and colder temperatures can increase the amperage drawn and therefore the wattage used significantly A sustained current draw above 5 Amps slewing or above 2 5 Amps tracking should be considered reason enough to rebalance the system and or to re mesh the worm gears At extremely low temperatures with a full load amperage draws can reach 3 Amps tracking and over 6 Amps s
69. ht and fully engaged If you accidentally move the axis too high and overshoot the angle it is better to loosen the four Polar Axis Lock down Bolts a bit bring the axis back down a very small amount and progress back up with the bolts hand tight This way you are using the weight of the mount to insure a solid connection to the altitude adjuster One full turn of the Altitude Adjuster Hand Wheel is approximately 0 37 degrees 22 arc minutes Methods for Fine Polar Alignment e GTO Keypad Please refer to the instruction manual for the GTO Keypad and read the sections from Getting Started through Alternate Polar Calibration Routines amp Tips Also be sure to read the Keypad Version 4 17 Addendum As time goes on the keypad manuals will be updated Please refer to the Technical Support section of the Web site for the most recent manual Here are summary descriptions of several techniques for polar alignment from the Keypad Manual and Addendum o The Keypad startup routine Auto connect NO provides two methods The North Polar Calibrate and the Two Star Calibration These two polar alignment methods were really designed for quick coarse alignment in the field with portable setups They are most appropriate for visual observers The Two Star Method is generally the better of the two as it is less affected by orthogonality issues These two methods are not really adequate for the type of usage we expect with the 3600GTO o The Day
70. ht does not necessarily signify low voltage from your power supply A number of things can cause the servo to go into this condition including balance issues and gear mesh but power issues should always be looked at first if the amber light occurs e Keypad resets The keypad will suddenly click and go back to the startup screen As voltage gets lower resets of the keypad become ever more frequent OK So what happens if you connect to a power supply that delivers more than 20 volts What about 24 volts i e two 12 volt batteries in series which actually delivers between 25 and 26 volts Here again there is no simple straight forward answer The biggest danger as your voltage climbs over 20 V is that the GTOCP3 and GTOELS boxes will overheat Again conditions will play a role Here are some considerations e First excess heat shortens the life of electronic components over the long term Too much excess heat from extreme over voltage will even damage the components and may burn up the unit right before your eyes e Second energy that is being dissipated as heat by the voltage regulator is basically being wasted e In addition at even higher voltages your motors may experience chatter from the excessive gain and there is an increased likelihood of damage to the motors encoders and system components not to mention the heat damage to the control box as voltages climb higher e The voltage that matters is the voltage that enter
71. il a star image EVEN if it has 10 degrees of backlash so that analysis is definitely suspect I m having a frustrating guiding problem with my mount and need to figure out my next steps Your next step would be to remove the camera and place a high power eyepiece with crosshair reticle into the focuser Then sit down and watch what happens to the guide star With the eyepiece and reticle you can see whether or not the mount is tracking smoothly and how the periodic error is manifesting itself Yes you will have periodic error and any good CCD camera will pick it up to give you oval stars that is a given What you need to find out is whether this periodic error is within limits 3 5 arc seconds for the 900GTO and 2 5 arc seconds for the 1200GTO or 3600GTO and whether it is smoothly varying You can also do some hand guiding using the 4 buttons on the keypad It will tell you how responsive the mount is to your guiding inputs and may even show some hidden problems when you try to keep the star on the crosshairs Alternately you can use PEMPro The full version of PEMPro is included with the 3600GTO to characterize your periodic error It will tell you things like the peak value and the smoothness of the error You can also characterize your mount tracking and guiding abilities using the Characterizing the Dec Motions test outlined in the Technical Support section of our AP Web site and included in the back of this manual Many tim
72. ional drift alignment or software solutions using your main instrument Tips on Making the Fine Adjustments to the System Azimuth Adjustment Fine azimuth adjustment is performed with the two fine azimuth adjustment knobs one on each side of the mount You must back off the opposing azimuth knob in order to turn the other adjusting knob that will push the stationary Azimuth Adjuster Block and therefore rotate the mount in a given direction The tendency is for people to back off the opposing knob several turns and then to turn the adjusting knob until you think you are aligned and finally to tighten the backed off knob to lock the azimuth in place Although this method is quick it is only recommended for rough alignment There is a better approach for accomplishing the very fine movements you are seeking at this stage We suggest that you try this method once you are very close It eliminates one of the classic problems of fine precise alignment You get everything perfect and then somehow the act of locking it all in place shifts something and ruins the alignment With the method below the two acts of adjusting and locking into position are combined You are effectively adjusting INTO the desired locked position Classic problem solved 1 First decide which way you think the mount needs to be rotated and determine which knob will push or adjust and which knob will back off 2 Both knobs should be somewhat tight against th
73. is inside the 3600FSA or pier If you have a pier that is rather tight you may need to attach the Azimuth Adjuster see the next step before securing the mount to the pier so that you can line the holes up by turning the mount s big square base 4 Attach Azimuth Adjuster Attach the 3600GTO s Heavy Duty Azimuth Adjuster to the bottom rear of the mount s bottom plate To do this first unscrew loosen each of the knobs far enough that the azimuth adjuster block on the bottom of the plate will easily fit between the ends of the two rods Install the Azimuth Adjuster Assembly as shown in the photo at right and fasten with the two 1 4 20 x 1 3 4 socket head cap screws that are provided with the Azimuth Adjuster Assembly Once the Azimuth Adjuster is installed you can snug the knobs up against the Azimuth Adjuster Block Now when you rotate the mount base within the pier it will turn the bottom part of the Rotating Pier Adapter If you were having trouble moving the base via the azimuth adjuster block alone this will allow you to line up the holes for attachment 1 4 20 x 1 3 4 Socket Cap Screws 2 5 Secure the R A Axis to the pier When you have the holes lined up fasten the mount to the pier top or 3600 Flat Prepare to Mount the Declination Axis ie Surface Adapter using seven 3 8 16 X 3 4 socket head cap screws and 3 8 flat washers There is not a tapped hole in the pier adapter plate immediately b
74. is well suited for a large refractor Newtonian Cassegrain Richey Chr tien astrograph or for multiple instrument imaging setups Your 3600GTO will most likely be installed in a permanent setup in an observatory It will probably carry a large and expensive instrument or more than one This will not be an installation that you will want to repeat Zenit because you made a mistake the first time We strongly suggest that you S o read this manual thoroughly Examine the mount s components carefully Northern x gt in a comfortable location during daylight Plan ahead as carefully as Hemisphere xe amp possible and get answers to questions before you need them Why Polar Alignment is Important Polar alignment compensates for the Earth s rotation If you were to take a long exposure photograph with Polaris often called the north star in the center of the field you would discover that all stars seem to revolve around a point near to Polaris This effect is due to the rotation of the earth on its axis Motor driven equatorial mounts were designed to compensate for the earth s rotation by moving the telescope at the same rate and opposite to the earth s rotation When the polar axis of the telescope is pointed at the celestial pole polar aligned as shown in the diagram at right the mount will follow track the motions of the sun moon planets and stars As a result the object that you are observing will appear motionless
75. lewing Higher voltage will help but at these temperatures slower slew speeds are recommended Some Power Basics for Non Electrical Engineers It is vitally important that you understand what is meant by adequate power Adequate power has two major criteria that must be satisfied adequate voltage and adequate current amperage Think of voltage as the pressure or push of the electrical energy Voltage represents the potential difference or electromotive force across a circuit More simply put voltage is how much the electrons desire to move through a circuit On the other hand think of the amperage as the volume or quantity of the electrical energy Amperage is more accurately described as the total number of electrons that move through the circuit over a given amount of time 32 Your 3600GTO s servo drive system needs energy that is pushing its way through the system at a pressure of at least 12 0 volts It will normally perform best if that voltage pressure is between 14 and 18 volts If the pressure exceeds 20 to 22 volts you may begin to generate heat buildup in the GTOCP3 and or GTOELS control box es as the unit s voltage regulator must dissipate more and more excess energy as heat Your servo drive system needs available current of 6 to 10 amperes Even though it only consumes around one amp during normal tracking and only about 1 5 to 4 5 amps when slewing at high speed under normal conditions it should have
76. lled 18 volt setup under normal load actually delivers roughly 2 1 volts x 9 cells 18 9 volts and a 24 volt system delivers 2 1 volts x 12 cells 25 2 volts A battery is considered fully discharged at about 1 75 volts per cell You do not ever want to discharge a battery below this level even if it is a deep cycle battery A 12 volt battery discharged to this level 1 75 volts x 6 cells 10 5 volts is totally insufficient to power the 3600GTO An 18 volt system consisting of a 12 and a 6 or of three 6 volt batteries discharged to this level still has 15 75 volts Results of Either Inadequate or Excessive Power So what happens if inadequate power is supplied to the mount The answer is a number of things Which of these happens first is hard to predict without knowing other factors Rest assured knowing that you will not damage or break anything by supplying inadequate power You will however spoil that evening s observing or imaging plans until the power situation is rectified Here then are the most common symptoms of a poor power supply e Alabored sound from the motors when slewing Be aware however that there are other things that can cause a motor gearbox to make strange noises e The power LED on the GTOCP3 turns from red normal to amber motor stall or safe mode or goes out completely When the power light changes color to amber the servo shuts down and quits trying to drive the motors A note of caution The amber lig
77. lts Auxiliary holes tapped 1 4 20 for cable ties amp accessorie d eeg A Spacing for 5 16 bolts 5 5 SET for 1 4 bolts Spacing holes tapped for 1 4 bolts 1 4 20 4 sets Astro Physics PlaneWave Dovetail Saddle Plate In cooperation with our friends at PlaneWave Instruments Astro Physics is proud to offer our 16 5 Dovetail Plate for PlaneWave DOVEPW This saddle plate was specifically designed for the proprietary dovetails of the PlaneWave CDK17 CDK20 and CDK24 telescopes This is the perfect way to marry one of their fine astrographs to the 3600GTO This saddle plate can also be mounted on our 1200 series of mounts for use with the CDK17 The plate attaches to the 3600GTO mount with six 3 8 16 socket cap screws Four clamps are provided to securely lock the instrument in place For the CDK17 and CDK20 you can also use with another smaller instrument As shown on the next page the plate will attach to the SB3627 for such an arrangement 16 DOVEPW 16 5 Dovetail Saddle Plate for PlaneWave Dovetail Plates 3600GTO this plate in a side by side configuration along Mounting Holes SB3627 3 2 3 5 Lock down O Spacing for 1 4 bolts 4 sets 4 5 AP Spacing for 5 16 bolts O An s UXiliary holes tapped 1 4 20 tes Or Cable ties amp a accessories 5 5 Am Spacing for 1 4 bolts n m 7
78. n leg of the cable will be coiled up inside the hollow R A shaft and will probably be situated all the way back against the R A rear cover plate To make it easier to access the Dec cable once the Dec axis is installed reach into the axis and carefully pull the cable forward and out of the axis Then re coil the cable into the R A axis posi tioned so that it will be easy to reach once the declination axis is attached DO NOT have any of the cable actually hanging out of the R A axis or it will get pinched when the declination axis is set in place The photo at right shows a good arrange ment 11 Mount the Declination Axis onto the R A Axis At 84 Ibs 38 kg the Dec axis is not quite as unwieldy Declination Axis as the R A axis However it must be lifted higher than Positioned for Mounting the R A You may still wish to employ a mechanical lift if available If lifting by hand we again recommend that you have two assistants to help you as described above two to lift one to guide 1 Check the Cables in the Declination Axis If you have ordered your 3600GTO with the optional limit Dec RA L switches 36LSS you will also have a cable coiled up Mating Surface gt lt inside the declination axis Make sure that this cable is not protruding from the mating surface of the dec lination axis As mentioned in the instruction above you do not want to pinch this cable between the mat Attachment ing surfaces of the two axe
79. n you are bal anced don t forget to securely tighten all the clamps The scope is balanced when it stays put does not move with the clutches loose and movement back and forth about the declination axis has the same feel in both directions Be mindful of eyepieces cameras and other accessories that are yet to be added and compensate accordingly Second Balance the Polar Axis l Now moderately tighten the declination axis clutches and position the mount with the telescope horizontal and the dec lination axis horizontal The counterweight shaft is now horizontal with the center of the counterweights the same height as the middle of the tube Loosen the R A clutch adjustment screws as noted above Again be careful because if your scope is significantly un balanced it may swing rapidly in the out of balance direction Move the counterweight s up or down to achieve the correct balance in R A Again movement back and forth about the R A axis should have the same feel in both directions Re set the tightness of all 6 clutches to the resistance you want making sure that each axis 3 clutches are evenly tight ened See section on clutches above Try to anticipate any balance problems due to the extra weight of cameras diagonals heavy eyepieces finders solar filters etc If the scope moves by itself when the clutches are loose then the scope is not balanced adequately You may want to tweak by carefully repeating the abo
80. ne symptom of an overly tight worm is a chattering sound as the motors try to slew at 600x or even as low as 300x You can check to see if the worm turns easily by removing the motor covers and then removing the large aluminum spur gear to get access to the worm end Try turning it by hand If it does not easily turn then the motor will also have a difficult time turning it Check in our technical section of the AP web site to learn how to set the worm mesh In real cold weather well below zero F it might also be a good idea to lubricate each of the spur gears and their sleeve bearings with a light machine oil When warmer weather returns this can be replaced with a light grease Lubriplate 105 which will reduce the wear factor during warm temperatures Third under extreme cold temperature conditions below 20F it may be necessary to replace the grease on the worm wheel teeth with a lighter material Our mounts use a special formulation of Lubriplate 105 with a damping grease added This combination is ideal for low wear since the damping grease portion allows the grease to stay on the teeth and not get wiped off by the motion of the worm Although this combination works well even at temperatures below zero it does get more viscous in really cold conditions We have tried straight low temperature greases that work to 80F but in each case the worm gears get abraded very quickly Using no grease at all is also not recommended for a GoTo system
81. ng the adjustment process If you notice a slight amount of shift particularly with a larger scope tighten the screws If you find too much resistance the screws may need to be loosened slightly n o Azimuth Adjuster Block The screws are properly set at the factory Most users with permanent installations will never need to touch them and we would generally advise you to leave them alone If you do feel the need to adjust these screws DO NOT over tighten them A x 5 2 The Azimuth Adjuster Use the two fine azimuth Nylon Tension Screws adjustment knobs one on each side of the mount to make adjustments You must back off the opposing s azimuth knob in order to move the other knob in the desired direction Please refer to the photo at right Note that the east west direction arrows on the photo below are for the northern hemisphere They will of Reference Mark course be reversed in the south Note also that you mY zy Oe can see the azimuth adjuster block through the sight window in the center of the Azimuth Adjuster body Fine Azimuth Adjustment Knobs The 3600GTO has approximately 14 degrees 7 deg of azimuth adjustment possible 7 West The knobs have been scribed with graduation marks and the body of the Azimuth Adjuster has corresponding Fa East Reference Marks by each knob Take advantage of D 3 these graduations on the knobs to mark your starting 4 S T Oe and en
82. not including counterweights Recommended for 20 and 24 Ritchey Chretiens and CDKs Please feel free to call and discuss your application with our staff Instrument mounting interface Declination hub has ten 3 8 16 tapped holes on a 12 000 bolt circle Diagram page 15 11 480 291 6 mm diameter Use of the Flat Surface Adapter S3600FSA is highly anced Weight of mount Capacity of mount Pier adapter base GTO SERVO DRIVE SYSTEM High torque zero cogging Swiss DC servo motors enclosed in machined aluminum housing 2000 tic quadrature yielding an effective resolution of 0 044 arc seconds per tic 57 6 1 gear reduction through a custom built set of large diameter fine toothed precision spur gears for vastly superior performance Servo Motor Control Box GTOCP3 Control Box removeable GTO Keypad to control all motor functions includes extensive databases and tour Hand held computer os ae features firmware updates via internet 0 4 to 0 8 amps at 15 volts tracking 1 5 to 3 0 amps at 15 volts both motors slewing at top speed of 600x GTO Keypad connected no load room temperature no optional Precision Encoder System or Limit Switch System therefore no GTOELS box Power supply requirements 15 volt DC at 10 amps recommended acceptable range 14 18V 5 arc seconds peak to peak 2 5 arc seconds or less in one worm cycle 5 6 minutes This maximum allowable error is fully tested and verified The PEM
83. nt device including most capture cards and webcams like the Philips Toucam Pro and Meade LPI The uncorrected periodic error of your 3600GTO will be 5 arc seconds or less when it leaves our facility We will have reduced this already small native error significantly by loading the error curve from our extensive testing procedures into the servo system The resulting error that remains should be negligible and will probably be satisfactory for all but the most demanding applications You can however reduce the error even further to maximize performance without auto guiding by recording a much longer run with PEMPro that will average more complete cycles of the worm The serious imager may wish to redo the PEMPro run once a year more or less depending on usage to compensate for gear run in If you ever remove your motor gearbox or manually turn the worm gear you will also invalidate any previously recorded corrections and will need to do anew PEMPro run Manually moving the telescope does NOT turn 41 the worm gear so that is not a problem Complete documentation is provided in the help menu of the installed program Also please read the Important Information HTML file on the CD before loading PEMPro onto your computer PEMPro uses the ASCOM interface to control the mount In addition to the functions available through the ASCOM interface PEMPro v 2 x and later also includes a very handy and effective Polar Alignment Wiza
84. oes not give satisfactory results e The mount will rarely be used as a portable mount e Other excellent alternatives are available that take advantage of the Astro Physics GTO system See further details below Altitude and Azimuth Adjustments Rough Polar Alignment To begin with your 3600 Flat Surface Adapter 3600FSA and or pier should already be oriented approximately towards the pole See the section earlier in the manual on pier assembly For rough polar alignment your goal is to be able to sight and roughly center the celestial pole when looking through the polar alignment sight hole in the center of the R A polar axis However we realize that unlike our smaller mounts this one will probably have most of its assembly and rough alignment work done during the day when the pole is not visible You may want to consider using an inclinometer like the one shown at right for rough altitude setting You might also consider making a mark of due north in your observatory for rough azimuth setting If you use a compass to set the rough azimuth be aware of the difference between the true pole and the magnetic pole for your particular location You must also be f careful of any magnetic effects of the mount s various components on your compass performance F mes F _Sight Hole To perform the rough alignment you will need to make altitude up down and azimuth side to side adjustments to the position of the m
85. ommend heavy duty deep cycle batteries designed for deep discharge applications The most common problems are due to inadequate power supply See the earlier section on Power Considerations The keypad reset or locked up when I plugged my CCD camera PC or other equipment into the same power source as the GTO mount was using Testing the power supply with a meter shows adequate volt age The meter is reading an average and will not show momentary dips Gel cells have internal resistance which will cause voltage drop when the load changes When you connect an additional CCD camera and PC the load may momentarily drop below 9 volts and the keypad will reset or it may affect the GTO circuit itself and cause the keypad to lock up We recommend that you use a large marine battery or golf cart batteries that are not gel cells and hook everything up to your battery pack before calibrating the GTO Or better yet put the other equipment on a separate battery or batteries What is the maximum voltage that can use to power the servo drive Please refer to the Power Considerations section of the manual For polar alignment am using declination drift technique with stars on east amp south Now do not see any drifts in declination on both sites E amp S so the mount should be properly aligned However have still small drift in R A which looks like the R A motor is a bit faster than earth rotation This drift is some thing like 1 5 arc sec
86. onnect the power cable to the GTOCP3 before you connect the keypad cable To turn the unit off simply disconnect the power at your power supply or battery Considerations for observatory installations We suggest that you disconnect your GTO Control Box from 110 V and any other device CCD camera computer etc when you are not using your mount so that if your observatory experiences a power surge or lightening strike your mount electronics will not be damaged If you operate your mount remotely you will have to leave your power cable connected just as you do for the rest of your electronic equipment You may want to consider surge protectors or other protective measures to protect from voltage spikes A disconnect relay to remove power from both the 12 volt and ground wire is highly recommended in this situation POWER Indicator Light This red LED will remain illuminated when your system is powered up and operating properly The red colored LED indicates proper functioning of the servo system If the servo detects a problem the LED will turn from red to amber An amber LED indicates that the servo has gone into safe mode or motor stall mode and is no longer trying to drive the motors The motors will be stopped Position data is not lost during this condition If the voltage falls below about 10 5 volts the power LED will go out completely The keypad will also not function properly below about 11 volts See the section on Power Consider
87. orks easily If you are in the southern hemisphere or cannot see Polaris in the north an inclinometer is probably your best bet 6 Continue your azimuth and altitude adjustments until you can sight Polaris in the center of the polar alignment sight hole or you are as close as you can guesstimate At this point you have achieved a rough polar alignment which may be sufficient for casual visual observations if you are not planning to slew to target objects with the keypad When the R A motor is engaged the power is plugged in it will compensate for the rotation of the earth and keep the target object within the eyepiece field of view Your target object will slowly drift since polar alignment at this stage is only approximate However you can make corrections with the N S E W buttons of your keypad controller For finer polar 23 alignment see the section later in this manual and the appropriate sections of the Keypad Manual 7 Tighten the polar axis lock down bolts with the 5 16 hex wrench If you will be refining your alignment further as we suspect you will only snug the bolts down Don t forget to snug the backed off Azimuth Adjuster Knob against the Azimuth Adjuster Block The Daytime Polar Alignment Routine in Brief The Daytime Polar Alignment Routine that is described in the Keypad Manual is also an excellent method for rough polar alignment It is especially useful in the southern hemisphere We mention it her
88. ough This is still much easier than removing a heavy instrument Once you have the cables arranged and the string in place carefully mount the DOVE3622 or DOVEPW or whatever saddle plate you are using onto the hub of the declination axis As noted above the cable channels of the DOVE3622 should be at the eyepiece camera end of the setup since that is where most of the cables are headed BE VERY CAREFUL that you do NOT pinch any of your cables between the plate and the declination hub As noted above your cables should be appropriately in two bundles one for each cable channel With the saddle plate in place give another look at your cable lengths just to be sure At this point you should have all of your cables and your wire pulling string simply hanging out the back of the right ascension axis You will now wish to feed these cables through the bottom opening in the R A Rear Cover Plate If you do NOT have the Limit Homing Switch or Precision Encoder Systems on your mount you can also choose the Opening opposite the one used for the servo cable Secure the R A Rear Cover Plate with the six cap screws you removed earlier Always check before tightening anything to be sure that no cables are caught or pinched Because of the virtually limitless number of cable configurations that are possible we leave it up to you to decide ona best solution for routing the cables out of the R A axis The blank Auxiliary Panel s can be left off
89. ount As shown in the photo at right the Azimuth Adjuster Altitude Adjuster and Polar Alignment Sight hole are all close together for convenience 21 The Azimuth Adjustment System The 3600GTO s Azimuth Adjustment System has two major components that combine to make adjustment of the azimuth angle precise secure and easy The Integrated Precision Adjust Rotating Pier Adapter is the foundation of the system The entire mount glides almost effortlessly on the azimuth bearing as the adjustment knobs are turned The Azimuth Adjuster Assembly makes for easy and accurate polar alignment in your observatory or in the field The heavy duty construction and integrated one piece design results in smooth control of the azimuth axis and secure locking of the azimuth angle once aligned Large left and right adjuster knobs are graduated for precise control of the azimuth position angle The size of the knobs makes them easy to turn with very little torque required even with the mount fully loaded The 3600GTO Integrated Precision Adjust Rotating Pier Adapter with Azimuth Bearing The Precision Adjust Rotating Pier Adapter consists of two plates that allow ultra smooth adjustments for critical polar alignment There are two black nylon setscrews on the underside of the Precision Adjust Rotating Pier Adapter These screws are used to apply tension to the rotating plate You may on rare occasions need to adjust these setscrews to gain the proper feel duri
90. own Attachment of the DOVELM162 is from the top for easier reposition ing if changing secondary scopes 17 Cable management Think Ahead The key to good cable routing is good preplanning Unlike a smaller mount you will not be inclined to simply pop off a 200 Ib instrument package to install or modify a cable Do it right the first time and then provide yourself with a means of adding or replacing cables using a trick learned from electricians that will be explained below If you have a custom mounting plate machined instead of using our DOVE3622 or DOVEPW be sure to keep cable management in mind during its design A one piece plate can simply have a hole in the plate above the center of the declination axis for cables if the instrument mounting permits this Any dovetail or two piece adjustable sliding plate will probably require something like our cable channels Mount Control Cables Servo Limit Homing Switch and Precision Encoder The 3600GTO was designed from its very inception to accommodate its required cabling inside the mount where it would not catch or tangle during normal operation Instructions for attaching the servo cable are detailed earlier in this manual Specific instructions for the Limit Homing Switch System 36LSS and the Precision Encoder System 3600GTOPE are included in separate documentation Accessory Cables Introduction to the 3600GTO Cable Management Capabilities There are of course man
91. r view of the pole obstructed e Computer Software Solutions There are many software packages that include aids to polar alignment Some work better than others Most of them have shortcomings especially if there is any orthogonality error or flexure in your system We have seen customers practically tear their hair out trying to get good alignment using software Do not be fooled into thinking that your alignment is perfect simply because a piece of software told you so Polar Alignment is after all entirely a mechanical issue With the creation of the Revised GTO Quick Star Drift Method Roland and other staff members here at Astro Physics no longer even bother with software for polar alignment Having said that here are some of the software options that are available o There is a Polar Alignment Wizard in the Full Version of PEMPro 2 x that is included with your 3600GTO This wizard is quick and easy and gives excellent results Think of it as the traditional star drift method at warp speed Details are in the PEMPro documentation o We suggest that you refer to detailed instructions in the GTO Keypad manual for a method that utilizes CCDOPS from Santa Barbara Instrument Group SBIG for precise polar alignment This method is basically traditional drift alignment with CCDOPS and your camera precisely measuring the drift for you 30 o There are also other similar alignment procedures including one in MAXIM DL from Diffraction Limite
92. rd a Backlash Analysis Routine and a StarFinder Routine The Astro Physics Command Center APCC We are currently under development with the Astro Physics Command Center APCC The APCC will add features and functions to the control system of the mount and will act as a serial hub for the use of additional applications Features include the following Virtual Serial Ports to connect multiple applications Customizable Meridian Limits that work in conjunction with an improved meridian delay feature Customizable Horizon Limits Highly Sophisticated Pointing Model and variable tracking for both axes 3 D viewer showing the orientation of the scope and mount for remote users Complete mount control including terminal interface Please keep an eye on the Web site and the ap gto users group for updates and details OPTIONAL 3600GTO LIMIT HOMING SWITCH SYSTEM 36LSS The Limit Homing Switch System for the 3600GTO is designed to enhance the safety of remotely operated imaging systems Instructions for the Limit Switch System and a wiring diagram with pin out information for a simple power cut circuit is provided in the 3600 Limit Switch System Documentation OPTIONAL 3600GTO PRECISION ENCODER SYSTEM ON THE 3600GTOPE The Precision Encoder System for the 3600GTO provides a level of tracking accuracy that sets a new standard for German Equatorial Mountings Instructions for the Precision Encoder System are provided in separate documentation
93. rer We advise that you determine your instrument s balance point fully outfitted with all planned accessories before attaching your rings and scope to the sliding bar or custom plate Large instruments of the type we expect to see mounted on the 3600GTO do not lend themselves to excessive trial and error ALWAYS attach adequate counterweights to your mount BEFORE attaching your telescope 25 Understanding the R A and Dec Clutches We suggest that you read this before assembling your system ie Why have clutches on the 3600GTO Clutched drive systems have many advantages over non clutched systems The only real disadvantage is that they cost more to produce Listed below are a few of the most important advantages of a clutched drive system in an astro nomical mounting o Clutches provide a convenient means of balancing the axes o Clutches do NOT require disengaging the worm gear from the worm wheel There are two major problems with mounts that require worm disengagement for free movement of the axes o Disengaging and reengaging the worm can result in gear mesh issues and backlash oe Disengaging a worm on an unbalanced load can cause damage to the teeth of both the worm gear and the worm wheel o Clutches are the last line of defense in protecting your expensive optical instruments from damage in the rare event of a servo malfunction or in the more likely event of operator error The drive system of the 3600GTO is ver
94. rol Box Additional information is provided in the special note under the Astro Physics ASCOM V2 Driver section below and a detailed technical description is provided at the end of the Troubleshooting section of this manual You must have two serial ports available on your computer to take advantage of this feature If you use a laptop or a newer desktop computer you will probably need to purchase a USB to serial adapter Starting in the spring of 2008 Astro Physics began offering single port and four port USB to serial adapters made by Keyspan that we have found to work quite well on our own equipment USB1P amp USB4P The serial ports on the GTOCP3 control box allow remote operation of your mount a handy feature for catching those winter pretties from the warmth of the house or for using the mount at a remote dark sky site that is miles from home For remote control of a mount that is within 100 yards or so of the controlling computer we have found the Icron Technologies USB Ranger 2204 USB extender available from Astro Physics in mid 2010 along with the Keyspan USB to serial adapters mentioned above to be an excellent solution The USB Ranger 2204 provides four USB ports one of which is used by the four port USB to serial adapter leaving 3 available USB and four available serial ports at the mount The Icron USB Ranger 2204 supports isochronous data transfer and will therefore work with most CCD cameras including those from SBIG with no appr
95. rosswise DOVE3622 for extra rigidity and security spacing used for large rings and Lengthwise interval is 1 000 riser blocks You will note that the standard lengthwise spacing for most of the ring sets is in increments of 1 375 This seemingly odd spacing was chosen to accomodate the 13 75 spacing that is an 4 500 6 875 8 220 5 500 7 450 Q Q Q oO Color coded circles represent the standard AP 3 200 diameter bolt circle Each circle connects four 1 4 20 tapped holes that are used when attaching the DOVELM162 in side by side configurations Each bolt circle is also associated with a pair of tapped 1 4 20 holes with 6 875 crosswise hole spacing for additional attachment points The bolt circles are spaced lengthwise at 1 375 intervals along with the standard ring sets An additional full set of six is also provided at each end for maximum separation industry standard for 15 to 16 plates which may be used on top of your instrument for accessories In addition this spacing accomodates the 5 5 crosswise spacing 4 x 1 375 of the DOVEPW in 51
96. rsion 5 x or higher of the ASCOM platform Special note We strongly advise that ALL Astro Physics GTO Mount owners use the TOP RS 232 port on their control boxes for connections to the ASCOM V2 driver As explained earlier the two RS 232 serial ports on the GTOCP3 control box are NOT identical Today s PC hardware and Windows operating systems no longer cater to serial applications The lower port is less able to handle the timing errors framing errors and noise that are often present in high data traffic applications like the V2 ASCOM driver when used on today s computers A more detailed technical discussion is at the end of the Troubleshooting section of this manual 40 Planetarium Imaging and Observatory Software from Other Vendors There are a number of planetarium programs that can be used to control the Astro Physics GTO Servo System In addition some software designed primarily for camera control and or observatory control and planning also have limited ability to control your mount Many of these use the ASCOM interface and will take advantage of the new V2 ASCOM driver mentioned above Any software that can use the AP V2 ASCOM driver will have extensive mount control capabilities because of the driver s virtual keypad features Other programs employ native drivers that the software designers wrote from our publicly available command set See your Keypad Manual The list that follows is certainly not exhaustive but cont
97. rt end of hex wrench we 2 Balancing Your Telescope For proper operation the telescope must be adequately balanced along both axes Start by balancing the tube assembly First Balance the Declination Axis de Position the mount for balancing Move the R A axis so that the counterweight shaft is pointing down The declina tion axis assembly will be in the meridian this is the classic photographic pose for a German Equatorial Position the Dec axis so the telescope tube is horizontal and pointing east Tighten the three R A axis clutch adjustment screws Loosen the three Dec axis clutch adjustment screws until they protrude about 3 8 to 1 2 9 13 mm from the axis hub so that the telescope moves freely about the declination axis Be careful If your telescope is significantly out of bal ance it may swing rapidly in the out of balance direction Loosen the tube mounting rings and slide the tube back and forth for balancing This is best done with the tube in the horizontal position If you are using the 22 Dovetail Saddle Plate slightly loosen the clamps on the female dovetail plate and slide the male plate and telescope to the desired position Be very careful not to over loosen the clamps so that the male dovetail sliding bar can tip out We suggest that you snug at least one of the clamps back up each time you go to test the balance Then loosen adjust and retighten as needed until balance is achieved Whe
98. s Holes 1 Dec R A Mating Boss raised surface a ae delice 2 Mount the Dec Axis The declination axis should first be positioned with the declination hub up and the counterweight CW shaft adapter down It will have Si b ight Hole been shipped and should be transported with the Cable Channeli declination mating surface bolted down to the shipping i crate It may be best to lift the axis into an intermedi ate position like a work bench and turn it over there Counterweight CW Then carefully lift the declination axis onto the R A Shaft Adapter axis keeping the Dec hub up and the CW shaft adapter down The Dec axis will fit into the mating surface of the R A hub If you have preset your R A altitude to 35 40 degrees as instructed above the axis will stay in place and will not fall off For safety sake however we recommend that you not let go completely until you have one of the mounting bolts started a od nk i T ISA iI Jot 3 Secure the Declination Axis The first step will be to align the three holes on each side of the declination axis with the corresponding holes in the mating surface of the R A axis If you pre positioned the R A mating surface as described above and you set the Dec in place with the Dec hub straight up i and the CW shaft adapter down they should already be very close a SD Carefully turn the Dec housing on the R A mating surface until th
99. s are shipped with lead free electronics R A and Dec Cable 10 pin Receptacle A Y cable and a 22 Servo Extension Cable with 10 pin connectors are both included with your mount The Y cable has been pre installed inside the RA axis and is attached to one of the plates on the rear axis cover with a receptacle Its connection to the declination axis is described earlier in the manual Attach the connector from the 22 Servo Extension to the receptacle and to the GTOCP3 Control Box 12V Locking Receptacle Place the DC power cord s 5 5 mm locking plug the cord is included with your mount into the 5 5 mm receptacle marked 12V on the GTO Control Panel and lock in place by screwing the plug s locking collar onto the receptacle Plug the cigarette lighter plug end of the cord into your power source The recommended voltage range is 14 to 18 volts A 15 volt filtered regulated power supply of 10 ampere or more rating like our PS15V10AC is ideal See the section entitled Power Considerations earlier in the manual for more details on adequate power sources There is no on off switch on the GTOCP3 although on off switches are found on most power supplies We recommend that you connect all of your cables to the GTOCP3 Servo Control Box before applying power whether from a power supply or from a battery Because of the relative locations of the receptacles when the GTOCP3 is attached to your 3600GTO you will find it easier to c
100. s bottom dovetail fitting Snug down the two thumb screws to hold the control box in place 3 Attach Servo Cable Attach the 22 Servo Extension Cable CABGTOR22 that was included with the mount to the control box and to the receptacle on the rear plate of the R A axis 4 Attach Cable Stays Slip the cable stays over the cable and attach to the polar fork using the buttonhead screws that you removed in step 1 Attach GTOCP3 and Servo Cable Loosen Thumbscrews Tilt in GTOCP3 Tighten Thumbscrews Y Remove Buttonhead Screws Connect Servo Cable y y The optional GTOELS control box for the Precision Encoder System and for software control of the Limit Homing Switch System is installed in the same basic fashion on the opposite side of the polar fork For detailed instructions see the separate documentation that pertains to the options you have selected 14 FINAL ASSEMBLY CABLE MANAGEMENT AND POLAR ALIGNMENT Attach Mounting Plate How you proceed at this point will depend entirely on how you will be using your system and on the instrument s and additional equipment that you will be using with your 3600GTO We strongly suggest that you read this entire section up to the sections on Polar Alignment before actually performing any of the operations that we outline below While we have divided this into sub sections out of organizational necessity you should keep in mind that most of the individual sub sections are intim
101. s is practical and perform a few minor maintenance tasks and your 3600GTO will give you many years of trouble free service Care Although we build it to be rugged enough for field use your 3600GTO is a precision instrument with very accurate worm and wheel adjustments Please be careful if you place the mount on a flat surface i e the ground or trunk of your car The gear alignment may be affected if the R A and Dec motor gear box assemblies sustain undue lateral force This is true of any fine instrument We suggest that you transport and store the mount in its packing crate or in a well padded box ALWAYS disassemble the mount before moving it or transporting it More damage can be done in a few careless seconds in transit than in many hours of normal operation It is always advisable to keep your mount protected from dust and moisture when not in use In a remote observatory situation this may be easier said than done However observatories generally have enough air flow to allow things to dry out well enough should you close up on a dewy setup On the rare occasion that the mount is used in a portable situation allow the mount to dry out before packing it away for storage once you get home On the other hand if it is cold and dry outside keep the mount packed up when you bring it into the house until it reaches room temperature to avoid fogging it up or simply leave it in the garage or some other unheated area The same advice applies
102. s the control box For example two 12 volt batteries connected in series producing roughly 25 to 26 volts that are 50 feet away from the mount in a truck might only deliver about 20 volts to the mount by the time the current has gone through all that hopefully very heavy gauge cable e Cold weather does two things It demands more voltage from the system especially for slews and it allows heat to dissipate faster At temperatures below freezing you may be safe with up to 24 volts but we do not recommend this as a general practice A far better practice for cold weather is to reduce your slew speed and thereby your voltage demands e lf using a supply with voltage over 18 volts you should periodically check the GTOCP3 to be sure it is not overheating Warm to the touch is OK Too hot to touch continuously is TOO HOT e Finally you should be aware that voltages above about 28 volts begin to pose a shock hazard to humans and an arcing hazard to electronics that are not designed for that voltage We have tested the 3600GTO in our facility indoors at room temp with 25 5 volts the equivalent voltage of two brand new fully charged 12 volt batteries connected in series We did not observe any problems at this voltage The mount performed perfectly and was allowed to track for several hours with occasional slews being performed to simulate a real world situation There was no chatter from the motors from excessive gain The GTOCP3 and GTO
103. sion on any cable once everything is finished and mounted but likewise there should not be excessive slack or slop especially on com ponents that are part of the imaging train You can always fasten excess cable length to the mounting plate especially to our SB3622 and SB3627 8 Arrange the cables protruding from the declination into two bundles depending on which side of the optical assembly they will be routed to Each bundle will be for one of the cable channels in the DOVE3622 If you have a custom plate bundle accordingly You can use cable ties or Velcro straps like those that we provide if you wish Remember that the cables must be able to flex and turn without binding as the mount points your instrument all around the sky 9 Now is the time for the electrician s trick Take a length of cord or heavy string and run it through the two axes DO NOT tie it or bundle it inside of the mount It must be free to be pulled back and forth inside the mount once everything is fully assembled Please note This trick will work for many cables that you may need to add however be realistic Cables with huge plugs Parallel DB25 s come to mind probably can t be added using this method Also the more cables you have inside your mount the more difficult it is to add yet another one You may find that it is easier to feed the wires from the R A axis to the Dec axis as they will make the bend into a larger opening rather than the reverse
104. t Surface Adapter 3600FSA This will be required for most of the pier options available to you e Counterweights 30 lb 30SCWT Up to 12 counterweights will fit on the standard counterweight shaft e DC Power Source 14 to 18 volts at 10 amps is recommended o BEST CHOICE Filtered Regulated Power Supply Household AC to DC converter we recommend our 15 volt 10 amp supply for users with 110 volt 60 Hz AC power PS15V10AC o See additional information in the Power Considerations section of this manual Many of these items will be discussed throughout these instructions Several additional options are available e Limit Switch System for the 3600GTO 36LSS Switch system for establishing safety parameters past the meridian and for homing functions e Precision Encoder System for the 3600GTO on the 3600GTOPE State of the art technology for virtual elimination of periodic error in real time Note This option can NOT be purchased as an upgrade after the mount is complete It must be ordered before the mount is built e 11 5 counterweight shaft extension M3655 For balancing heavier loads e Autoguiding Accessories Most imaging and CCD based autoguiders can take advantage of the 3600GTO s autoguider port The autoguider port receptacle RJ 11 6 uses the industry standard SBIG ST 4 wiring setup e Extension cable for keypad Please call Astro Physics to obtain a quote on the length of extension cable you need Note on
105. t pier can have an open top with an 11 500 inside diameter and eight holes 0 500 down from the top as shown in the drawing at right See the cautionary note below e For portable use we are currently offering the ATS 12 Portable Pier This robust portable pier will be fitted with the 3600 Flat Surface Adapter e Other portable piers may also be available from other manufacturers Any portable pier that you choose must either accept our 3600 Flat Surface Adapter 3600FSA or else adhere strictly to the specifications provided above and in the drawings at right We recommend that your pier employ our 3600 Flat Surface Adapter for best results e For occasional portable use with light loads a 10 diameter pier like an Astro Physics or ATS Portable Pier may also be used Simply attach a 1200 Standard Pier Adapter 1200SPA to the 10 pier without the Mount Lock Knobs the Azimuth Adjuster Block and the Center Pivot Screw Now bolt the 3600 Flat Surface Adapter onto the 1200SPA using the tapped holes for the lock knobs and center hole and you are ready to go Cautionary Note As noted above we strongly advocate the use of our 3600 Flat Surface Adapter in your installation This is primarily due to the issue of less than perfect tube roundness in virtually all available pier materials The mount s integral pier adapter is machined on a lathe and is as perfectly 3600 Flat Surface Adapter 3600FSA Bolt hole pattern and
106. ten the screws with the short end of the hex wrench to reduce the available leverage Dec Servo Cable Inserted Servo Cable Cover Plate Removed Cover Plate Replaced Through Axis Port Cable Attached to Servo Optional Limit Homing Switch Connect the declination section of the Limit Homing Switch Cable if applicable See separate instructions on the Limit Homing Switch System You do not need to actually connect the cable at the R A Rear Cover Plate at this time but you must be sure that the cable has been fed down through the Sight Hole Cable Channel opening in the Dec axis and into the R A axis for future connection This should be done before you block access to the hollow shaft with a mounting plate 13 Attach the GTOCP3 Control Box optional GTOELS Limit Switch Encoder Box and Cables The GTOCP3 control box is attached to the built in bracket as shown below This will be on the west side of the polar fork for those in the northern hemisphere and the east side of the fork for those in the south The procedure is illustrated below 1 Prepare the control box bracket Begin by removing the two small buttonhead screws near the back edge of the fork using a 3 32 hex wrench These will be used to attach the cable stays once the servo cable is attached Next loosen the two thumbscrews on the top of the bracket until they are flush on the bottom lip of the bracket 2 Attach GTOCP3 Tilt the GTOCP3 Control Box into the bracket
107. that slews at high speeds The wear on the worm and wheel teeth is extremely high and can cause very high periodic error to rapidly develop due to scratches and high spots that develop on the gear teeth At this time we have no solution to ultra low temperatures Tests Last night it was 8 F here and I tested several of our 900GTO and 1200GTO mounts in the observatory Two are very old from the original batches and one is brand new All worked well at 600x but showed signs of laboring at 1200x slewing used a 12 volt marine battery to power them replaced the marine battery with a variable power supply that varied from 12 volts to 18 volts At 12 volts when both motors were slewing at 1200x the power draw was in excess of 8 amps in summer this is around 2 5 amps The motors were laboring and not running smoothly at full speed turned up the voltage to 15 volts and the current draw dropped to around 5 6 amps The motors worked smoothly at 1200x with no hesitation at that voltage level would recommend for cold weather work to get a supply that can deliver 15 16 volts at a rated current capacity of 10 amps Higher than that is not necessary Above 18 volts is not recommended for the 900GTO or 1200GTO 43 MOUNT CARE CLEANING AND MAINTENANCE Like any fine piece of equipment your mount s longevity and performance are directly correlated with the quality of the care that you give it Handle it with respect keep it as clean and dry a
108. three half tight all three fully tight etc In order to feel the effect of the clutches you may wish to experiment with your assembled mount before attaching the instrument Assemble the mount with the mounting plate and counterweight shaft Do not put the telescope and counterweights on at this stage With the above assembly with the clutches as shipped you can feel the amount of force needed to move each axis by hand Grab each end of the telescope mounting plate and move it with a backward and forward movement of the Dec axis Get a feel for the amount of resistance to this motion Perform the same operation on the R A axis by moving the counterweight shaft backward and forward Now loosen the clutch adjustment screws until they protrude about 3 8 to 1 2 9 13 mm from the smooth surface of each axis You should be aware that the clutch adjustment screws have spring loaded tips These tips continue to provide some pressure on the clutches even though the adjustment screws feel as if they are no longer engaged To fully disengage the clutches the adjustment i screws must be backed out this 3 8 minimum distance Move the 2 axes as you did above and feel the amount of resistance This is the least amount of resistance that the system will allow and it is how you will want the system set for balancing Clutch amp Disengaged Finally carefully tighten the clutch adjustment screws until you feel them bottom out
109. time Routine See Polar Aligning in the Daytime is a great trick for daytime setup It is also the recommended first step in fine alignment of the 3600GTO as well as the recommended first step in alignment for anyone with any Astro Physics GoTo mount in the southern hemisphere o The original GTO Quick Star Drift Method of Polar Alignment that takes advantage of the Meridian Delay feature of the Astro Physics Servo System is also included in considerable detail in the Keypad Manual A table of suggested stars is found in Appendix of the manual o Saving the best for last we have also included a second Revised GTO Quick Star Drift Method that was conceived for use with a finder scope This method is detailed in the Keypad Version 4 17 Addendum and includes a one page Quick Reference Sheet to use once you are familiar with the method By using a finder scope you are able to remove orthogonality issues from the process making subsequent alignments much easier For our testing purposes here at Astro Physics using one of the first production 3600GTO s we obtained accurate enough polar alignment for extensive imaging with a focal length of 3810 mm using the Daytime Routine followed by the Revised GTO Quick Star Drift Method and did so in less than one half hour The combination of Daytime Routine followed by the Revised GTO Quick Star Drift Method is our recommended procedure for anyone in the southern hemisphere or anyone who finds thei
110. treme temperatures and conditions please contact Astro Physics first Your 3600GTO has more than twice the capacity of our venerable 1200GTO and employs a much more powerful servo motor on each axis Actually we were so impressed with these motors that we also adopted them for the 1200GTO as well starting in 2011 The R A axis may be moving loads as heavy as 700 pounds instrument counterweights Dec axis weight These loads put even further demands on the power system supplying the mount Above all the 3600GTO has a very large worm gear that is meshed into an appropriately large precisely machined worm wheel These state of the art components make contact over a much larger surface area than smaller worm systems of lesser precision The large worm gear and worm wheel contribute to the 3600GTO s incredible performance but they are also capable of generating significant drag on the motors and demanding higher current than smaller mounts This is especially true when temperatures drop and lubrication is at a higher viscosity When you consider this mount s overall performance and capabilities it is truly remarkable that it can do so much on so comparatively little power As the table below shows the 3600GTO rarely uses as much energy as a Single small incandescent light bulb The high efficiency of the Astro Physics Servo System makes portability and remote operation a real possibility for this mount We want you to get the most out of t
111. ve steps after everything has been attached to the telescope Be especially careful loosening the Dec clutch knobs 28 Polar Alignment Part 2 Fine Polar Alignment If you plan to use any of the go to functions of the 3600GTO or do astrophotography you must accurately polar align Procedures will be discussed here These procedures require that an instrument be attached to the mount However that instrument does not need to be the main scope that the mount will carry You may find it much easier to perform the alignment with a finder scope or a small wide field instrument that is attached with adjustable guidescope style rings so that you can make the instrument precisely orthogonal to the mount We recommend the following general procedure for accurately polar aligning your 3600GTO 1 Perform a rough alignment as described earlier in this manual 2 Perform the daytime polar alignment routine using either a small telescope or a finder scope The daytime routine is detailed in the Keypad Manual 3 Perform one of the GTO Quick Star Drift Methods a Use the Revised GTO Quick Star Drift Method if you have a finder scope or a small refractor that is mounted in adjustable guidescope rings This method is found in the Keypad V 4 17 Addendum b Use the standard Quick Star Drift Method if you are using an instrument without adjustable rings This method is also detailed in the Keypad Manual 4 If needed refine further with tradit
112. weight s recessed knob and slide the weight into position The brass pin that locks the counterweight onto the shaft is spring loaded so Counterweig ht Lock it is not necessary to worry about holding the counterweight with the knob Knob facing down Always use two hands to attach or move a counterweight on the shaft The recessed knob minimizes the chances for accidentally snagging or loosening the knob during your session 3 Re attach the safety stop to the end of the counterweight shaft This will help to prevent injury if someone accidentally loosens the counter weight knob NOTE A firm tightening of the counterweight knob will not damage the surface of the counterweight shaft The pin that tightens against the stainless counterweight shaft is constructed of brass Safety Stop Attach Mounting Rings and Scope The 22 and 27 Dovetail Sliding Bars SB3622 and SB3627 As noted in a previous section the 22 and 27 Dovetail Sliding Bars are drilled to allow a wide variety of mounting rings or instrument mounting hardware to be attached Attach the rings in a position that provides the best combination of stability and balancing travel for your particular instrument Detailed drawings of the different hole patterns found on these two sliding bars are found at the end of this manual Custom Mounting Plates Attach mounting rings to your custom mounting plate in accordance with the specifications of the ring and plate manufactu
113. xes Itis to eliminate all unwanted slippage The differ ence is important First and foremost BALANCE your system as well as you can See specific instructions below Perfection in balancing is not necessary for the servo drive system as the mount can easily handle several pounds of imbalance but the less imbalance you have the less requirement you have for extremely tight clutches In other words the required clutch tightness will be directly related to the amount that you are out of balance Clutch tightness will also be deter mined by how you are using the mount and how much total weight and moment arm you are moving with each slew Long exposure astro photography will demand tighter clutches than visual use as will very long or very heavy systems You can Safely tighten the clutches to roughly 5 to 10 ft lbs of torque on each adjustment screw but if you need the clutches tighter than that you should consider re balancing We have found that tightening as far as we can using the short leg of the hex wrench gives a very satisfactory level of tightness Moving the axes even at this level of tightness will not damage the clutches You will also not damage the clutches by tightening as hard as you can with the long leg of the hex wrench that was included with the mount but we would not advise using a cheater bar or longer l handled hex wrench Again for best mount performance the clutches Tighten with should all be evenly tightened sho
114. y The axis itself pivots on two bearings on each Center Pivot Bolt You should NEVER loosen the Center Pivot Bolt as part of your polar alignment 29 It is possible for the mount to shift slightly when the Polar Axis Lock down Bolts are fully tightened down after adjustment of the altitude angle by turning the Altitude Adjuster Hand Wheel For the rough alignment procedure earlier in the manual this shift would have been of no consequence Now however we are after more precision To prevent that shift it is suggested that the initial altitude adjustment at this stage be done with these bolts hand tight and as you approach the final adjustment point tighten the bolts a little further with a hex key after each movement You cannot move the mount with the Polar Axis Lock down Bolts fully tight but they can be quite snug and still allow a small final movement into position Considerable effort may be required on the last nudge or two to finish the alignment Since you will be making adjustments against ever increasing resistance from the Polar Axis Lock down Bolts you should always make your last few adjustments going uphill so to speak with the Altitude Adjuster Hand Wheel being turned counter clockwise If you try to adjust down the Polar Axis Lock down Bolts may actually hold the axis slightly above its rest position against the adjuster thereby allowing it to settle in the future By lifting it up into its final position everything is kept tig
115. y more cables in the average imaging setup than just those used to operate the mount Dew heaters motorized focusers camera rotators CCD cameras guiders and other accessories all require their own cables often two one for power and one for computer interface and these cables can become a nightmare They tangle up they catch on everything they sag and cause flexure and they are just plain unsightly hanging haphazardly off of a beautiful mounting with a fine optical instrument perched gracefully on top With the 3600GTO you can route all of your cables through the mount turning the nightmare into a dream come true SB3622 A Cable Attachment on the SB3622 or SB3627 The cable routing system begins at the top literally with the design of aaah wan E Oe ee the optional 22 Dovetail Saddle Plate DOVE3622 and the SB3622 O and SB3627 22 and 27 Dovetail Sliding Bars Down each side of A a gt at Si gt 4 4 the SB3622 and SB3627 are a number of 1 4 20 tapped holes that are eee e p Se ee intended for attaching cable stays strapping down CCD power supplies 1 4 20 Tapped Holes spaced every 2 or dew heater controllers or for attaching any other accessory device 10 holes on each side of the plate that you use Attaching your cables and other danglers to the plates Ce ee ee ee ee e will greatly help in the reduction of the dreaded differential flexure that For attachment of cables power boxes
116. y powerful If the system is not capable of slipping there is considerable potential for damage What do they do The three R A and three Dec clutch adjustment screws depicted below and in the assembly diagram at the begin ning of the manual have the function of connecting the R A and Dec axes to their respective drive worm wheel gears Their function is progressive from no tension axes relatively free to move as required during correct balancing of the telescope to a virtually locked up state When you move your telescope by hand via the clutch system clutches loosened you are NOT turning any of the gears The motors do not turn The servo cannot update the pointing posi tion of the system The servo does however still know the exact position of the worm gear itself since it has not moved and therefore maintains its periodic error correction phase It is not possible to move the axis with the clutches and thereby also turn the worm and reduction gears How can you find out what they really do As shipped all 3600 mounts have all three R A and Dec clutch adjustment screws set flush with the outside surface of the axis This will give a moderate level of tightness clutch action Clutch adjustments are made with the 5 16 hex wrench from the included set At this point you must bear in mind that for optimum performance all three clutches on each axis R A or Dec should be tightened evenly with the same tension i e all
117. ystem the keypad with its digital display screen and the included PulseGuide and PEMPro software all combine to offer extraordinary sophistication for today s observer Optional precision encoders for real time periodic error elimination and limit switches for safety in remote observatories are available as upgrade accessories when the mount is ordered Whether you enjoy visual astronomy exclusively or plan an aggressive astrophotography or CCD imaging program this mount will allow you to maximize your night out under the stars The advanced keypad features allow you to slew automatically to objects in a wide range of databases as well as any R A Dec coordinate A large selection of common names for stars and other objects makes your selection a snap The rapid slew rate of 2 5 degrees per second 600x allows you to locate objects very quickly and accurately You will be very pleased with the intuitive operation of this keypad There are no complicated sequences of keystrokes to remember It is so easy to use that even if you don t use it for a few months you will feel at home with the keypad very quickly The keypad is only one way of controlling the versatile Astro Physics GTO Servo System From its very conception the servo controller was designed to work with any software that was written to use our published command set We do not lock you into any proprietary software or mandatory additional equipment To increase the versatility

3600-GTO-2011-0531-w.. - Astro

Contents

Download Pdf Manuals

Related Search

Related Contents