Zenith B50M88W 50" Rear Projection Television
Contents
1. MODEL CHASSIS KEYWORD SYMPTOM CURE Unit had defective DX3409 DX3408 DX3407 AND DX3406 All diodes Unit keeps on blowing the main line fuse FX4301 opens as ___ shorted in power supply Replacing diodes returned the set to normal A19A20D GA1 Power Supply soon as power is attached to the unit operation A25A11D GA Audio Unit has low audio when adjusted to max volume replace r833 and R853 with 1 2k ohms A27A12D GA Audio Unit has low audio when adjusted to max volume replace r833 and R853 with 1 2k ohms Zenith A27A23W Unit Unit has an intermittent loss of vertical sync during specific scenes that have explosions or A cap need to be changed at ICX2200 pin 39 from a 10 mfd to a 1 mfd This A27A23W GA vertical bright flashes in the screen is the video input to this IC and too much capacity was chosen for this input Checking the source of the 200 vdc B we found that R3277 a 2 2 1 2 watt ohm resistor was open It was replaced where it promptly open even though Unit has bright screen with retrace lines Unit only has 56 ther was no apparent shorts on it s cathode Diode DX3287 pn 103 326A volts at the cathode of the CRT Monitoring the voltage at was replaced even when it checked good along with the resistor and A27B35W GA2 Bright screen CX3296 we found only 61 volts everything was restored to normal Looking at CX3296 on the top of board there was some staining around the Unit has heavy retrace lines then shut2. IQB27B44W_ ICB shut down CB Chassis set and in models intermittent shutdown problems Replace bead Inductor TX3415 with new part number 149 549 1QB32B42W_ CB shut down CB Chassis set and in models intermittent shutdown problems Replace bead Inductor TX3415 with new part number 149 549 IQB32B44 CB shut down CB Chassis set and in models intermittent shutdown problems Replace bead Inductor TX3415 with new part number 149 549 IQB36B42W_ CB shut down CB Chassis set and in models intermittent shutdown problems Replace bead Inductor TX3415 with new part number 149 549 Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM IQBS50M90W ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM IQB50M92w ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM IQB55M90W ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM IQB55M92W _ ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU Auxillery When using a DVD playe
3. Dead 22 1 2W QX3401 121 1348 all defective 1 2W along with the regulator STR53041 Z27X22D Unit has a symptom of a pulsing picture Unit has an intermittent symptom of loosiong horizontal sweep then the picture goes dark then on again Unit will not stay on long enough for 1 complete field to be displayed Tech monitors the Horizontal output B and finds it fluctuated from 130 Z32X31D GX shutdown volts Horizontal Driver The power supply is stable Unit has had a defective CPU ICX6000 Zenith Z32X31D Unit stuck in the wrong level mode and Z32X31D GX system control jcannot adjust the Set to Level 1 Zenith label and set the vertical parameter 11 from 35 to 40 Using STR53041 Regulator Always replace CX3413 22mf 63V CX3416 100mf 25V RX3404 180k use 1 2W Also check RX3407 47 ohm 1W Rx3408 22 ohm 1 2W QX3401 121 1348 use ECG184 or one Unit has no life at all We have had several of these all having Jof many other transistors with similar spec s listed in the ECG guide under no power no click from the ON OFF relay or the Degausing TO 220 and TO 220J case styles 4 only A 1Amp rating is required If that Z32X31D GX Dead Relay doesn t do it replace ICX3431 STR53041 This module will not allow the tech to change the level settings to Level 2 Zenith SY2518RK Unit was dead Tech replace the main when the Factory mode is turned on and the Jumper is on 4G3 pins 3 and 4 Z36X31D Gx Dead module a 9 1584 and now has no audio This chassis requir
4. Install software upgrade kit part number 800 01210 this includes a B5O0M88WA ZP88 OSD controls and possibly under other conditions EPROM main CPU and OSD CPU Problem can be seen at C2224 minus side The luminance is compressed When playing a video or a DVD in the composite or S video during the high white portions of the picture When freezing the DVD during input the set will loose vertical during a high brightness the explosion scene video and sync flatten Where at C2224 side the video C32A24T CA Vertical sync display Like when an explosion is being played back is not compressed Replacement of C2224 a 1mfd 35vdc cured the trouble poor short distance operation of remote caused by energy H2733DT GXC Remote efficient lighting Replace I R receiver with p 162 00041 Auxillery make sure that plug 9P4 is plugged into scan converter Circuit board and not H3241DT GXC Inputs Computer input not working the R F module check service menu item 14 is set to 1 cycling on an Unit would cycle on off for 15 min or so and stay for the rest of the day This symptom would only occur when set was H3246DT CS off cold Replace C4103 with a 22 07759 30 1Q3557CC GX dead 1Q3557CC Unit is dead Needs the power deflection module 9 1673 01 Zenith 1Q5270DT Does not respond to any functions from 1Q5270DT C8 Remote remote Replacement module not in correct vendor mode Stuck in factory mode
5. Poor washed out pix Milky Looks like bad CRT at first Jat 3 watt corrected the symptom Thanks to Bill Arnold Manticia Cal SR2573DT Serial 522 62390044 Unit has a loose shadow SR2773DT Cll purity mask Tube was replaced 3 months ago This tube will be under warranty A63ACTO01X SS2733LK 481 23081115 Unit will not produce blue on the CRT face place Jumping all three CRT cathodes together will SS2733LK Cll Missing color not achieve a B W picture Just a pink picture Unit has a defective CRT A68ACTOOX The video outputs were replaced 2SC5147 original number Parts sent out a SY2522RK GX raster SY2722RK serial 681 32431171 Unit has a green raster 2SC3229 Asked tech to check all the voltages at the CRT socket All voltages are Poor B W SY2549S serial 721 42250498 Unit has poor black and white within normal constraints with the exception of the G1 voltage at the CRT SY2549 GX tracking tracking Tech calling in for CRT replacement which was at 130 vdc instead of 18 vdc Unit had a open Q2205 Recommend to replace the audio MTS decoder board Replacement of the SY2588S GX Audio Unit has intermittent audio loss in 1 channel MTS board corrected fault PN 9 1589 01 Dead set Fuse FX3402 open or opens when main module is On jack pack look for a shorted IC804 check between pin 9 and ground if SY2768 GX Dead replaced resistance is low or 0 ohms replace IC804 Units using the 9 1583 amp 9 1612 Series modules possible no SY2768 GX no startup start up of p
6. a horizontal line across the screen The tech needs to check the power supply voltages at the power inputs of ICX2200 Pins 9 26 46 amp 48 It was discovered that we only had 9 volts on pin 26 Pins9 46 amp 48 were low Checking the 9 volt switched supply we found the 15 volt switched Z20A11 Unit will not turn on Unit will shut down supply was OK on IC3441 IN but nothing at the o IC3441 OUT It should Z20A11 GZ shut down immediately have been the SW9 volts supply Defective IC3441 221 166 09 Unit has several problems in the configuration mode Level was set to 1 when Zenith Z20A21D Unit has no audio All boards are repair it should be at 2 Also 25 C Type of chassis was at 0 when it should have Z20A21D GA Audio only items Boards must be serviced to component level been at 5 Resetting the parameters corrected the fault Buzz or impulse noise is coincident to the VITS VIR signals that are broadcast in the vertical blanking interval At the instant of the impulse noise Zenith Z25A02G serial 821 23020089 Unit has raspy buzz there is a pulse on or near Line 17 21 of the composite video measured at Z25A02G GA Audio in audio when receiving specific television stations Q1203 E The problem was C121 I had tech get into alignment parameter 14 and increase level from 42 to 58 This is used for the composite audio level adjustment The audio output is Customer complained about the low level audio from only 1 watt per channel not a power house It shou
7. ecessary to replace the CRT A68ACTOOX Note It has been discovered the cause of the arcing has been attributed to the Dag coating coming off inside the picture tube This coating SL2722LK Arcing in the Neck of CRT at turn on Also no is conductive and if it migrates to the neck off the tube it will cause cause SL2722RK C2 arcing green arcing back through the low level video drive circuits SL2743LK no serial Unit has no Blue or red Also the tube is SL2743LK C8 Missing color jdark Checking the cathodes of the Set will need a new CRT A68ADGO0XX Poor B W SL2784BT black and white tracking of off Shorting the SL2784BT C8 tracking cathode Unit will need CRT A68AGD00xzx SM2722RK serial 481 22515088 Unit has no green Shorting all three CRT cathodes will not achieve a black and white SM2722RK C10 Missing color picture TV needs replacement CRT A68ACTO0X The set will have a haze to the picture that will mimic a In this case the tube was replaced but the symptom remained the same If a crosshatch pattern were put on the screen the vertical lines would be absent RGB only defective CRT In this case the picture was a Red haze on the Suggest the tech check the following resistors R5110 R5111 R5112 all SM2745MK C8 missing 1 screen Could not achieve good black and white tracking 120K ohm 1 2 watt Replacing them corrected the symptom I had tech check the B at the horizontal output t
8. es the module to be set to Level 2 This module will not allow the tech to change the level settings to Level 2 Zenith SY2518RK Unit was dead Tech replace the main when the Factory mode is turned on and the Jumper is on 4G3 pins 3 and 4 Z36X31D GX Dead module a 9 1584 and now has no audio This chassis requires the module to be set to Level 2 Zenith Z36X31D Unit will not turn off unit is always on A 9 Cannot set the level adjustment to level 2 Unit only has level 0 and 1 This may only be a minor problem I had tech go into the tech menu and set the Factory mode to 1 And look at the parameter of A C on off feature It was set to 0 This feature needs to be set at 1 It is used only when the television Z36X31D GX system control 1813N was replaced for a dead set symptom is switched on and off by an external AC switched source Was it happening when the power is turned on is the set is tring to turn on It has B and Drive at the horizontal output transistor but the power supply is going into ocer current shut down Suggest the tech remove the high voltage lead from the HV block ad stick thhe high voltage end of it in a glass coke ZA8Z83D Unit will not turn Tech replaced power bottle or equivelent to prevent it rom arcing to stratigic areas on the chassis supply deflection and signal modules but still cannot get the We found that high voltage returned Unit has a defective HV block A ZA8Z83D GZ no turn
9. ife the flare should not occur This is not an unusual PV4660VK C8 smear which corrected the fault situation Tech wondering what else would cause this defect I asked if any video PV4663RK yellow spot on lower right hand side of screen games are played on this TV Yes there is Removal of screen and viewing PV4663RK C8 Colored Spots Tubes changed earlier in year for same trouble inside lens of CRT shows a burned square in the blue CRT Unit fades to black with a no raster symptom then will fade This condition took about 40 seconds for the picture to completely disappear The problem was a loose filament supply for the CRT s on the Deflection PV4663RK C8 amp Raster back on power supply board Unit is dead Deflection board 9 1302 07 is burned around the The tech will have to replace the flyback or board It is more economical to PVR4660 C8 Dead fllyback transformer area replace the deflection board assembly This television has no convergence correction Missing 16vdc PVR4663RK C8 convergence at connector 7C3 pin 6 replace RX3210 open and CR3206 shorted PVY4665RK After setting the convergence the STAR button was hit accidentally instead of QUIT Once this was done tech could not get into the tech menu to set convergence In order for the tech to gain access t the tech menu again the tech must push again All normal key entries do not gain access to the SURF TV QUIT Then access ca
10. io circuit problem in Power Supply module Replace Power supply and restored normal operation I was able to help Shop tech on SD2769 Unit has audio but audio gets distorted when the the repair of this unit It is a 1983 model television Unit had power supply volume is in the higher range Seems to mute the audio on defect causing the 26 vdc supply to be only 11 vdc The tech needs to check SD2789 B3 Audio voice peaks Power supply voltage the filter capacitors in the stand by power supply Unit won t fire up B is ok 12 v standby ok Pressing switch will not turn nothing happens model no SG5245y chassis no 9 592 4 SG5245Y Cl on SMPS seems to be working ok CX3439 a 4 7mfd 35 vdc was open J2722LKS serial 381 16091450 Unit has no blue on the CRT face place Jumping all three CRT cathodes together will not SJ2722LK C2 Missing color achieve a B W picture This set has a defective CRT A68ACT0O7X Tech will need to replace the main module and the CRT A68ACTOOX Note It has been discovered the cause of the arcing has been attributed to the Dag SL2722LK 381 22302030 The television was dead but when coating coming off inside the picture tube This coating is conductive and if it the tech installed the Main deflection board the Tube violently migrates to the neck off the tube it will cause cause arcing back through the SL2722LK C2 arcing arced over and took out the Main module again low level video drive circuits Whit the arcing symptom it will be n
11. ld EPROM and can be easily transferred by removing old the PVY5265 GZP convergence convergence and other adjustment on chassis microprocessor board and installing it to the new board PVY5265 GZ CRT leaking Blue CRT leaking coolant on main deflection board Unit will need replacement Blue CRT and main circuit board Unit has no video no OSD and a slick rasterwith an Red Unit has an open R3242 100K 1 2 watt resistor located behind behind the PVY5265 GZ No Video Green and blue horizontal lines at the top of the screen flyback under a Large power resistior Unit has smeary blue registration and tracking Blue CRT is The set also had smeary blue which had the very common open R5103 the only one with the defect Moving the Green socket to the 120K resistor on the blue CRT board This condition could happen on any PVY5265 GZ Smeared video blue CRT give a clear blue registration ane of the CRT boards When monitoring the B s on the deflection board it was discovered all the supplies are normal But after checking the input for vertical drive to the deflection board on connector 3G2 2 we found no vertical drive This should PV Y5265RK Unit has no raster When the G2 is rasied up the be a 5 volt p eak to peak narrow pulse at 16 6666 ms Tech will have to CRT will illuminate with 2 horizontal lines near the center of replace the 9 1713 module This module only comes with all the all of the PVY5265RK GZ raster the picture daughter boards attached PV5265RK Uni
12. ld not be expected to have Z25A11S GA Audio speakers Cannot get high enough audio from set a big sound from these low output devices All television using modules 9 1789 9 1790 9 1827 9 1829 9 1831 9 1832 9 1833 and after replacing the original 175 2721 tuner with a new 175 2721 tuner and the picture is Change RX3417 from 680ohm to 220ohm 1 2 watt the new tuners have Z25A11S GA tuning snowy or black slightly different operational parameters in the AGC circuit Unit will need the CRT A68AGD02X Note It has been discovered the cause of the arcing has been attributed to the Dag coating coming off inside the picture tube This coating is conductive and if it migrates to the neck off Z27X22D 721 45467024 Unit has an arcing in the neck of the tube it will cause cause arcing back through the low level video drive Z27X22D GZ arcing the CRT Shorted the video output drivers circuits I had a dark screen only when I use the tuner input no screen or speaker noise of any kind Everything else in the TV worked just fine like input from the A V jacks OSD menu etc Tuner voltages were fine too I suspected the tuner and replaced it big mistake That did not solve the problem So I went back to basics and started taking voltage To my surprise I found that video processing ICX2200 marked TA1242N had very low voltages all over its pins I checked the B to the IC and it was zero That basically solved the problem I traced tha
13. n be made to gain access to the tech PVY4665RK GZP menu convergence menu through normal means Customer needs to turn off the StarSight function In the clock ment the PV Y4665RK serial 621 15451192 Customer had subscribed customer needs to set the Time to Pacific time and turn auto clock to OFF to StarSight whereas the TV had the StarSight decoder built in Reset the time I had tech try setting the clock to 11 59 PM and wait for a few to allow the viewing of a type of TV Guide information The minutes and see if the clock reads the correct time after these few minutes customer has now discontinued the servvice but cannot keep after 11 59 pm The clock did indicate 1 03 am and appeard that it will Star Site the clock from reverting to Eastern time After the clock operate normally The tech will put in the correct time and will call customer PVY4665RK GZ GemStar reaches 11 59PM the set will indicate 3 00 AM automatically tommorrow Dark Raster top looks like rainbow no video no OSD slick raster with three R G B bowed lines across the top of open resistor R3243 100k 1 2w located just behind the HOT under a PVY5265 GZ convergence _ screen larger power resistor Tech looking for a quicker way to do these adjustments Recommend the tech remove the CPU and EPROM module from board assembly and install the old original CPU and EPROM on main module The memory is still retained Tech changed main module and now has to completely adjust in the o
14. on set to turn on 17196 05 R4163 and R4160 are burned These resistors are in the B supply for the convergence output supply An over current situation must have occurred in order to burn these devices out Since the convergence output board and convergence power supply are new and the new resistors are burning up the only thing that makes sence is that one of the sub deflection yokes convergence yokes may be damaged causing this over current situation to Z60Z83D 781 16351245 Unit was way out of conergence exhist Suggest the tech measure the DC resistance of all the windings in the Replacing the Converrgence output amp Convergence power sub deflection circuit All like windings should measure the same exact supply module did not correct the symptom Instead R4163 amp resistance All vertical windings should measure the same and so should the Z60Z83D GZ convergence R4160 burned open again horizontal Z60Z83D unit has no chroma in the PIP mode Unit functioned fine up until the signal module was replaced Now after 1 year the customer noticed the PIP has no chroma Z60Z83D GZ PIP Customer never used before this time Tech needs to order the PIP module no audio no no audio or video normal raster also you can view the ZB2797P Digital video customer s menu but not the service menu Replace IC3 on the ZCU BD
15. ower supplies at low temperatures Replace RX3299 62 ohm resistor with a 47 ohm 1 2 watt resistor Symptom customer menu breaks up or tears set turns off within 30 sec set turn on but will turn off if given a command SY2768 GX OSD from either keyboard or remote Replace D6003 on main module SY2788DT serial Unit has a sever purity distortion on the left Tech did not elaborate about the type of video that he saw on the screen Whether it has bright areas of the screen or if it was not related to high SY2788DT GZ purity side of the screen brightness conditions Tech is asking for CRT replacement approval Problem is caused by the setting of AFT hold parameter is not high enough SY2788DT Unit looses AFT lock on channels 16 42 48 amp The parameter has a range of 1 through 7 This set had to be placed on 7 in SY2788DT GX tuning 55 Customer is on CATV order for it to correctly tune these no standard signals SY2788DT unit does not have proper AFT correction Unit is running into a AFT search instead of locking into the Tech had to get into the factory menu mode and setup the AFC and Band SY2788DT GX tuning channel immediately settings The set had good sound and no raster or OSD Has high voltage and deflection Unit will get full raster if G2 is SY3288DT GZ Raster increased R3234 a 110k resistor off pin3 of the ihvt was open Checking the out vertical output we found that we did not have any vertical output Only
16. r the customer may complain of a IQB56W10G ND 991A Inputs ghosting on trailing edges of some items Tech needs to enter the service mode and change the change C trap to 0 Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM IQB60M90W ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU IQB60M90W Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a A ZP90 OSD controls and possibly under other conditions EPROM main CPU and OSD CPU Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a IQB60M92W ZP88 OSD controls and possibly under other conditions EPROM main CPU and OSD CPU Auxillery When using a DVD player the customer may complain of a IQB64W 10W ND 991A Inputs ghosting on trailing edges of some items Tech needs to enter the service mode and change the change C trap to 0 Appears the tubes may be bad again Unit runs about 18 hours a day every day This puts a lot hours on these tubes These tubes will run about 2000 hours then begin burning phosphor and requiring more drive to produce the Projection Television Unit has red and blue horizontal smear same amount of light As long as the G2 voltage maintains the same voltage Horizontal Like a comet tail CRT s replace just less than 1 year ago throughout the tube l
17. ransistor which was fine I Unit had no high voltage and would not turn on at all After _ then had tech inspect both boards had all the connectors filled After the main and power deflection modules were replaced the set inspecting the top side of the board and checking the foils side of the board it No still would not turn on but a distinctive click was heard that was discovered the connections to the base of the Horizontal output was not SM2745MK8 C8 Highvoltage _ was not present before touching the foil Resoldering this connection corrected this television SM2789BTS8 serial 421 00327074 Blurry picture when SM2789BT C8 Focus adjusting the focus the brightness will fluctuate Unit has defective CRT A68ADGO0XX SMS1935S Unit is dead Main module has shorted SMS1935S C6 dead Horizontal output transistor Suggest the Main board be replaced 009 01244 CRT A68AGDO00XX is defective also the main board Note It has been discovered the cause of the arcing has been attributed to the Dag coating coming off inside the picture tube This coating is conductive and if it SR2738RK_ 581 46173214 Unit is arcing in the neck and migrates to the neck off the tube it will cause cause arcing back through the SR2738RK Cll arcing caused the main deflection to fail low level video drive circuits RX3237 had increased in resistance from 2 2 to 4 ohms Causing the Picture Filament voltage to be about 2 volts Replacing the device with the a new 2 2 SR2738RK Cll Washed out
18. s down Unit only has 44 capacitor It s ESR was over 1000 ohms In otherwords open Replacing A27B35W GA2 Retrace lines _ volts at the cathode of the CRT CX3296 had only 77 volts CX3277 corrected the symptom 10 mdf 250 vdc Unit has slight convevergence mis alingnment Tech calling in Tech needs to hold the menu button down and when the screen changes after to find out how to get into the dynamic convergence 4 to 6 second press 9999 the Enter It will now be in the Dynamic A56M91W GZ convergence alignment mode Convergence setup mode Unit has narrow raster with blooming if a bright screen Regulated B not very stsable Ranges from 130 volts to 103 volts Replace B27A24Z5 CA Regulation appears or one operates the Brightness control CX3416 primary side of smps Order anew pip module 9 2110 Or repair it by rerouting the grounding as B27B40Z CB PIP Loss of pip for sets made weeks 25 32 of 1999 per instructions Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a B50M88W ZP88 OSD controls and possibly under other conditions EPROM main CPU and OSD CPU This is a B line projection set made by Hitachi if set cycles on off when plugged in look at the 32vdc led for the audio Check IC401 pin 9 Vcc for shorted condition also check E997 fuse for a open B50M88W ZP88 shut down supply if not lit with the rest of the leds replace IC401 Random characters appear in OSD when adjusting the volume
19. t B back and found C1233 470ut 10v leaky I replaced it with a 470uf 16v I thought a 10v cap is too low to filter a 9v supply However that did not bring the voltage back I tested L1208 which is connected to C1233 and to the 9v regulator 1C3441 and it was open I forgot to mention that my first test was actually on that 9v regulator which was fine I bridged L1208 with a very low value Z27X22D Raster missing measurements resistor just for testing and viola Thanks for all the help Bill I had tech check the Q5102 and compare reading to te other two transistors Q5101 Q5103 Q5102 has a F B reading on 0 1 on a fluke 77 meter in the diode mode This reading indicates the transistor is leaky and does not have the typical 0 6xx F B reading like the other transistors Tech replaced the Q5102 but still had green screen with retrace lines After checking the three RGB drive signals The tech found the R amp B drives at connector 2C5 1 amp 3 had 2 2 volts on them where as 2C5 2 had 3 7 vdc Measuring the RGB output pins of ICX2200 19 20 21 had all the same voltages on them Each of Z27X22D Unit has excessive green screen with retrace lines these test points should be the same voltage if a all snow pix is displayed Z27X22D GX retrace lines Tech calling in for CRT approval Unit also had a open Q2205 NO RELAY CLICK Checking RX3407 47 1W RX3408 Suggest also replacing CX3413 22 63V CX3416 100 25V RX3404 180K Z32X31D GZ
20. t looses the tuning of several channels PVY5265RK GZ tuning Extremely intermittent Suggest the tech replace the main CBA 009 Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM RBSOM88WA ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU Random characters appear in OSD when adjusting the volume Install software upgrade kit part number 800 01210 this includes a EPROM RB60M90W ZP90 OSD controls and possibly under other conditions main CPU and OSD CPU These are not retrace lines but the Auto CRT Bias pulses There is a Capacitor that needs to be removed from the 9 605 module to correct this problem REMOVE C2113 LOCATED NEXT TO 3K4 CONNECTOR IF SD2735 DIGITAL retrace lines Unit has colored retrace lines at the top of the picture capacitor is removed the condition stops Problem not in audio circuit problem in Power Supply module Replace Power supply and restored normal operation I was able to help Shop tech on SD2769 Unit has audio but audio gets distorted when the the repair of this unit It is a 1983 model television Unit had power supply volume is in the higher range Seems to mute the audio on defect causing the 26 vdc supply to be only 11 vdc The tech needs to check SD2789 B3 Audio voice peaks Power supply voltage the filter capacitors in the stand by power supply Problem not in aud
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