Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống
1
/ 75 trang
THÔNG TIN TÀI LIỆU
Thông tin cơ bản
Định dạng
Số trang
75
Dung lượng
761,96 KB
Nội dung
QUESTION: Sony KV32XBR95S TV had a good picture, until it stopped powering up. I found a shorted diode in the audio section and replaced that. Now the set powers up but without any picture at all. Sound is fine. The picture tube and the associated drivers look fine, but there is no video signal. Tracing back, I see the video jungle chip isn't putting out anything but it looks like it does not have the proper inputs. Tracing further, it looks like there is something amiss on the "P4" board which is the COMB filter. Service manual shows a part number 1195065 for the board, and the board has both 1195054 and 1195045 stamped on it. The schematic for the board does not match the circuit on my version of the board, so I cannot really troubleshoot at the component level. The two ICs on the board are discontinued Sony parts. I would like to replace the board but Sony says they do not carry a replacement anymore If you replaced D1410 in the audio circuit, also replace Ic140 the audio amp and your set will power up once again. Strange but true! In the future when looking for help always give the part numbers that you have already changed, it makes it easier to look up the repair QUESTION: Sony KV27TS27 TV. After working for a month since the first replacement of Q601 and 602 including the h.o.t. Q502, they broke down again. I checked all of the surrounding components and they all measure o.k. I replaced the parts and the set played for one week then failed again. The supply to the set is 123 V AC. How sensitive is the set to voltage drops and dips? Could the F.B.T have a problem? Check T604 and R607 a .1 ohm 1/2 watt (goes way up in value) QUESTION: Sony KV2781R TV originally took more and more time to turn on. Eventually, it took up to 30 minutes or more, and then totally quit coming on at all. I found a defective surge resistor (220 ohm/25W), and a shorted horizontal output. Now there is a wavy green channel display and volume display when activated. The sound is OK, but no picture. Voltages are about 60% lower than normal. 200V is around 90V There is a .47uf cap in the horizontal drive circuit (on the base of driver?) that can cause this problem QUESTION: Sony KV 27 TS 27 TV. Q601, Q602 and Q501 were damaged. I replaced them with no succes. The relay on the set comes in when I plug in the set and then drops off again. When I try to start it through the power button same thing. I checked the entire power supply and everything is o.k. I checked all the components I replaced again and they are still O.K More than likely R607 a .1ohm 1/2 watt res. is open. Also check q603 QUESTION: Sony KV20TS27 TV. All channels show static for at least 5 minutes in colder weather. Higher range (50+) available before lower range. Video in appears unaffected. Tuner replacement or bad connections? If tuner, source? Connections within the tuner, you may try removing the tuner and resoldering all the ground tabs connecting to the case from the pcb and checking for any other suspicious connections. Tuners available fron Fulton Radio Service in Lansing, MI QUESTION NO. P12159: Sony Trinitron KV32TS36 TV the original owner stated if a fan blowing on it from the back was on it would keep the picture. I found a loose solder connect at the C board. I replaced the solder and it was fine for about 6 months. It came back with the picture going on & off frequently. I removed the cover again noticed the same solder connect loose and resoldered Suggest replacing the component that you are resoldering, throughly clean the leads and solder pads before installing it QUESTION NO. P12155: Sony KV 27TS27 TV came in with Q601 and 602 damaged. The horizontal out Q502 was also damaged. I replaced them but when I plug in the set I can hear the protect relay click. Also when I power the set by means of the power button, the protect relay engages and the set shuts down (0.5 sec). I rechecked the components I replaced and they are still good. Also is there a way to test the FBT? A good FBT ringer can be used to check the fbt without actually replacing it. Check for vary fine ring cracks around the driver transistor, driver transformer, horiz output transistor and FBT. Also any of the other components in the H deflection may need to be checked. A X 10 or more magnifier may be needed to see the ring cracks. Seems to be a common problem. Does the horiz output or FBT get quite warm when you try to start the set? QUESTION NO. P11309: Sony kv27ts27 TV has perfect picture but w/out sound when coax cable is hooked up to the back. But when VCR or DVD is hooked up using audio/video cables, the set works perfectly (w/ sound + picture) Look for small green circuit board labeled sbx1637xx. Probably has leaky capacitors. DO NOT attempt to repair, just replace. Available as generic from several suppliers for reasonable price QUESTION NO. P11238: Sony KX2501 TV. Need a value for C1902 on cb 1.602.173.11 (burned so badly can't read any id.) (might be the same as C1906 on 1.602.172.11) C1902 is a 330pf @2kv capacitor. Sony p/n is 110232700 QUESTION NO. P1233: Sony KVM14U TV. I need the value of and power rating of resistor R852? The one I've removed has lost its color bands, and used to glow orange when in circuit! ;( The first anode (G2) voltage was low at 190V and R852 was smoking. D852 was leaky (Sorry, I don't know the type) and R852 1k ohm was burnt out. Fitting replacements restored the G2 to 880V QUESTION NO. P11181: Sony 27XBR10 TV. B+ is down to 4 volts. There is no HV, and there is a loud, highpitched whine. I have 167 volts at the output of D601. I am trying to figure out how the feedback loop works. There is .4 volts across the IC652 LED, and Q651 is cut off. When Q651 is cut off, is that supposed to make IC651 increase or decrease the transformer voltage? Is there a data sheet for the STRS6301A available? Which is the primary of the transformer T651? Pins 5 and 8, or pins 2 and 3? This is the second time the set has failed with the same symptoms. I didn't fix it last time. The guy said he replaced the power supply. I presume that means the F board, but I don't know for sure. The set operated normally for several months after the first repair. Just before it failed, it would occationally drop HV for a couple seconds Suspect the regulator ic, also check the horiz driv transformat and flyback for very small ring cracks. You will need a good magnifier to see them, probably even a loupe. I would go with the ic and do the connections for sure QUESTION NO. P9228: Sony KV27HSR10 TV. The horiz freq is too high. I replaced ic301, the only voltage off is on pin 30 of ic301. It is 3.9v instead of 3.0v. Incoming hori sync pulse are clean I suspect the surface mount resistor/about the same location where you got your horizontal sync. pulses. It is a 1/8 watt surface mount with a value of 1.8k ohm. But I would advise to use a magnifying glass. Please note that is on the upright board beside your jungle IC. Remove the board that has horiz. sync. pulses on it and you should find it . It may have a 183 written in tiny print/or similar QUESTION NO. P8182: Sony kv32xbr26 TV, what kind of voltage should I get on the flyback terminal (low voltage side)? Is it ac or dc? When I try to measure it on +15v I did not got any voltage before the diode. I measured the diode resistance, on forward is ok except on reserve. I got only 330 ohm (ru30a diode), is that normal? Negative, Forward can read moderate resistance but reverse should read effectively infinity. Take the diode out of the ckt @ check both fwd and rev readings. The other end of the coil in the FBT is probably grounded. If there is a low resistance load on that particular supply you will read it rather than the true condition of the rectifier QUESTION NO. P9142: Sony KV20XBR TV has no output from the speaker jacks. Power amps seem fine, I suspect that perhaps in the service menu, if there is one, that the audio may be turned down or perhaps there is a way to select speakers off Check the bias voltages to the audio ic and for cracks in the solder connections where the speakers [leads & connector] physically connect to the pwb. Try connecting another set of speakers, of proper impedence, to the terminals QUESTION NO. P934: Sony KV2765R TV. Picture and sound fine from video and audio input. But when cold, no tuner image or sound. After 30 minutes or so, tv works fine in tuner mode. Sometimes tuner works for 23 minutes when I first turn it on, then fails and comes back after 30 minutes Tuner replacement may suffice QUESTION NO. P7292: Sony KV32HSR10 TV with horizontal tearing at the top. The horizontal drive signal had severe jitter. While probing around I accidentally zapped the horizontal output IC (STRS6301A) and I need a source for it. Two of its pins were dead short. I need to fix the short first, before I can get back to the original problem. Right now I only heard the relay 'click' after turning it on with no sound & picture Fulton Radio Supply in Lansing, Michigan is a Sony authorized distributor, I know that there are others. Scope the drive signal from the ic, thru the driver, to the gate of the output to see where the jitter and tearing is coming from Sanken's STRS6301A is available from B&D Enterprises (800458 6053) and MCM (8005434330), among others. One could also sub ECG/NTE 7046 QUESTION NO. P7268: The convergence of Sony KP46S55 (4 years olds) is bad after the TV was turn on for approximately 10 minutes. The blue color is horizontally displaced to the left about 2 inches. The cross lines for convergence adjustment were merged to form a perfect vertical white line. The horizontal line is also white except about a half inch at both ends have the yellow/orange colors I troubleshot the pincushion problem and found out one of the three power amps in the IC1704 was internally shorted to 16V at its output (pin #10). This explains why the fuse 902 was blown. Also the blue convergence problem was caused by the lose solder at pin #24 of IC 1705 QUESTION NO. P7217: Sony KV32S15 TV has sound but no picture (including OSD). High Voltage is OK. Video OK to CRT and I can hear Horizontal sweep circuits. Voltage at pin 5 of CRT should be 460 volts and is 175. Pins 7 and 8 of the CRT are at zero volts (DC to ground). Schematic shows 200 volts (on each?). 135 volts at TP91 is correct I have since found the problem. R701 (680K) is in series with the screen voltage control and was open Additional note to Sony television service tip, had similar problem with KVKV 27exr10, difference was that the tv would come on and play correctly sometimes for about one hour and THEN the screen image would become black for the first 1/3 of the picture or the first 4/5 of the picture. Problem could be mistakenly diagnosed as a vertical deflection problem QUESTION NO. P7206: Sonykv27ts27 TV, cannot select between tuner and video inputs. Also sound is always fron aux inputs Corrupted data from/to MPU or memory ic. Failure of MPU or Memory ic, failure of descrete device on one of the data or i/o lines QUESTION NO. P729: Sony KV27TS20 TV color spot problem, only has actual true color in each corner of screen. The rest of the screen is offcolor, fleshtones are highintensity greens, for the most part. Rotating the unit does not change the spots intensity. However, placing compensation magnets in various locations around the tube will extend the correct color areas out a bit. Is the tube hashed? Have you tried a tube degausser? Usually random color spots are caused by a stronger magnet that was too close to the tv, ex.stereo speakers. If a degausser works turn set off and back on. If the colors are still gone you are fine. But if they came right back check your fround loop strap that circles the back of the tube. Check for cracked solder joints where the loop plugs into the board also. If the colors do not go away or the tv looks like it has been dropped, the tube most likely has gone bad or been damaged internally QUESTION NO. P685: KV 27xbr37 TV shut down, only repeated clicking sounds happen when it is plugged in. Have checked HOT, HOT transformer, power converter transistors, voltage regulators, in and around the horizontal circuit and power supply circuits. Fuse is not blown and flyback and yoke checked for their respective resistance according to the schematic values, OK . No visible signs of cracks or bulging in the flyback and or any electrolytic capacitors . Lifted the B+ to the Horizontal circuit and the clicking stopped and you hear the two relays click on with low but clear sound from the TV program the cable box is tuned to. Have checked the circuit starting from the B+ was lifted all the way to the end (Flyback transformer output) and cannot find any defective parts. Found one odd thing in the audio output section, where a transistor 2sa1309a has a 30v at the emitter and 29.3v at the base,exactly according to the schematic did not have a voltage of 29.9v at the collector , it measured 0.7v but when I pulled the transistor out of the circuit it checked good with the ohmmeter. Also found the voltage at the Power converters (Q601 & Q602) emitter and collector respectively high as compare to the schematics value of 160, it measured 227V Bring up the set at reduced voltage. If it works troubleshoot power converter for the cause of too high voltage at Q601/2. Check voltages/supplies derived from FBT for s/c. Ring FBT. Replace supect 2sa1309a but check collector circuitry for s/c and drive to base QUESTION NO. P6225: SONY KV32xbr50 TV. Fuse is okay. The relay clicks when applied power. Set dead, no functions, no high voltage. Replaced IC651 (strs6301A), set worked for 1 minute. Then main fuse opened. Ic651 short between pins 123. Replaced IC651 again, along with C654, C613, C652, Q604,Ic652 and q651. Set worked for 1 minute, 135 volt is ok (when set was working). the original IC561 is strs6301A. I wonder if strs6301 (without the letter A at the end) will work STRS6301A is the replacement for STRS6301, and was designed to withstand higher temperatures than the original version, so it is NOT recommended to replace the "A" version with the plain version. This IC puts out a lot of heat even under normal conditions. But the lowercapability IC is unlikely to be killed by heat in only one minute's time, when properly heatsinked, IF there are no other faults QUESTION NO. P671: Sony KV27s25 TV with sound but no picture. It seems to have high voltage for a split second but then HV shuts down. I believe the set is going into current protection since the high voltage shutdown circuit is not being turned on Possible the regulated B+ to the sweep circuits are too high or the caps in the horiz yoke return ckt have changed value. Also make absolutely sure the connection at the flubask and driver transformers have been cleaned and resoldered. These connections have been a cause of many a quirky problem QUESTION NO. P6710: Sony KV27V36 TV. Replaced the flyback and H.O.T. Now the set will not power up. There is 160v but no low voltage. It appears that Q601 & Q602 are shorted out Start by checking the small red/blue caps around the smps transformer. Replace the chopper transistors with SONY ORIGINAL components. Remove the horiz drive transistor, drive transformet, horiz output transistor, and flyback. Thourghly clean the leads of the components and the ckt board where they mount and reinstall them. Ring cracks at the fbt and driver transformer have been causing a large amount of these types of failures QUESTION NO. P646: Sony KVM2120E TV, power supply B+ too high, 135 v and it should be 119 v. I checked and replaced all the caps on the ps, the regulator STR54041 and the fbt Are you certain the B+ from the regulator is initialized at 119 and not 135? Seen a lot of Sony teles and the normal B+ seems to be around 130,135. Try the set on a good variac and lower the input so your B+ is at 119 and see how the set functions. I will wager the set will have reduced width. Bet you have another deflection related prob QUESTION NO. P5267: Sony KV27TS27 TV that developed muffled, flat audio. It used to resolve itself after 30 to 60 minutes, but now it does not. Treble and bass adjustment with remote have no effect. Also, CRT elements are now arcing the length of tube neck every 30 to 120 seconds which sometimes shuts down set. Are these problems related? No, crt problem not related to audio symptom. New crt should fix arcing problem, MTS assembly or processing ic should take care of audio problem QUESTION NO. P5176: Sony KV27V55 TV. No picture no sound,and no power. Found Q602, Q601 and Q591 Hout shorted. R607 open. Replaced Q601,Q602,Q591,VDR602, VDR603, R607 and Flyback Trans. Worked for 1 hour and then made a loud snap, same problem again You did not mention if the replacements semiconductors were original Sony parts or generics. Seems Sony teles require original parts in these specific areas. Also, check the small red capa in the smps and derived ps circuits. Check for poor solder connections at the horiz driver transistor, transformer, horiz damper diode, horiz output, and flyback Remove old solder from flyback transformer and horizontal drive transformer and resolder. Apparently Sony had a service bulletin on that problem a while back. Also, if VDR's checked bad, check R644 and Audio Out IC. And finally, resolder anything that looks suspect in horizontal drive and output circuits. This should prevent all those expensive parts blowing again QUESTION NO. P5131: Sony TV 32XBR25, no picture, no sound, no high voltage. When the tv is plugged in, the relay RY601 turns on and off. All the components in the power supply check ok, same in the high voltage Check the vertical output circuit, the pincushion circuit, and the video output devices. Any of which can cause the set to sense a problem and initialize protect. Also, if the crt has a problem, aka arcing or intermittent interelement shorts, it will destroy the video outputs and cause shutdown QUESTION NO. P5107: Sony kv32s26 TV, has sound, high voltage but no picture and the power led blinks Check the video output devices [3] and the vertical sweep ckts. Occasionally the crt arcs that can fry the output devices. When the protect senses the defective video device it will not allow the set to go into full operational mode QUESTION NO. P486: Need value for R568 for Sony KV2020E TV Value of resistor is 18Kohm 1/4watt Taken from Sony KV2720 manual QUESTION NO. P3225: Sony kva3411 d. The television is giving a red spot in the left uppercorner because of a magnetic field. If I move a magnet on the top of the television a can get the spot away. If R155 1 or 1.5 ohm QUESTION No. P11145: Sony KV27XBR51, no video or audio from tuner RF input, and no monitor output. Has RF noise with no raster. Works fine if input to video 1 , 2 or 3 then also get monitor out OK. Does not seem to be the tuner or the IF, testing with a tuner sub. Bad VIF module, resolder AFT coil inside module, inspect other solder joints while you are there. Replace with new module if this does not fix it. QUESTION No. P11213: Sony KV2781R TV, the picture was foldover and only about 5 inches in middle of screen and also reduced the horizontal size. I had checked the vertical frequency, it went up and alway changed about 200hz to some Khz. Sounds like main regulator IC STK3035 is not working, check 135v at output of regulator out TP. Also check shunt resistor 200 ohm 20W, low supply voltage will cause vertical circuit not to work properly QUESTION No. P861: Sony KV2781R TV. I need the original number for the horizontal output transistor 2sd1497 Sony pt.# 872930090 QUESTION No. P425: Sony TV KV25XBRII Television demonstrates intermittent behaviour. Screen shows reduced luminance then can be returned to normal by physically jarring television. Suspect cold solder joint or defective oscillator crystal somewhere in video signal path. Audio is normal Check the video delay line DL301 on the A board. A very common problem in this model is a cracked solder joint on the legs of the delay line QUESTION No. 21963: Sony KV1397R 13" color TV with intermittently drifting tuning. When problem shows, all channels are still available, and with plenty of RF gain, but drift toward the nocolor direction (not toward the grainy color direction) until finally the AFT voltage from SIFVIF module begins cycling. Tuning follows. Gets stuck in this cycling mode which lasts several seconds per AFT cycle. Only one AFT signal is active at this time, I believe the 'down' side. No action at all, even when changing stations, from the oPosite AFT signal. Schematic gives no help to one as unfamiliar as I with the theory behind this tuner's control loop ANSWER 1: In answer to my own question, tuning loop appears to work like this: Control IC tells tuner desired channel, tuner responds, control IC watches AFT UP and AFT DOWN signals from VIFSIF module to decide whether correction is necessary. In this case, VIFSIF module is sending erroneous AFT down signal until control IC makes a decision that it's too far off ideal channel frequency, so tuning to center channel, at which time incorrect AFT down signal again tells the control IC to detune tuner. Shorting the input to the AFT DN IC, which is isolated from the VIFSIF by a P22K resistor stoPed the hunting, but in the meantime of course killed any AFT action. Replacing VIFSIF ($44!) cures the problem ANSWER 2: The problem you are experiencing is caused by bad connections in the SIFVIF module. To repair the problem, remove the IF module from the main board and remove the shield case from the IF module and solder the internal pins and any other bad connections you can see on the pc board. Then reinstall the shield and solder onto the main board ANSWER 3: Two common problems on Sony can cause this problem. Both are bad connections. The most likely, from your description is a bad solder joint in the tuner. You must pull the tuner, remove the sheilds, and check the joints where the sheild and cage are soldered. These crack. Carefully, resolder all grounds. The other is in the if can. Open the can and resolder all connections on the agc control, and grounds on the board QUESTION NO. P1251: Sony kp61v25 projection TV has sound but no picture. Sleep timer flashes on and off all the time. Crts are not on but power is getting to them. The problem started a year ago with the picture turning blue then back to normal after a few seconds then to picture blanking out for a minute. Had to turn set off then back on to regain picture. The IK circuit is killing the video, set is designed to do this to protect the tube(s). Take it to a tech that is familiar with Sony projection, you may have a bad tube, HV splitter, etc. Sony projection units are not a place to start for novice techs, if you must play with it yourself be SURE to use SONY parts NOT generic replacement parts QUESTION NO. P11168: Sony KPR46EX32 projection TV, red gun projects a sharp horizontal line across the screen, about a third of the way from the bottom. Below this line there is no red picture projected. After about 20 minutes a red horizontal line flashes across the center and the video shuts down completely, but sound continues. After turning off TV and waiting 10 minutes, TV will project video for a shorter length of time, then repeat the problem. Red convergence also a problem at the top corners, but fine in the center. home.mindspring.com/~wa6ati/ then go down the page and look for Sony TSS logs QUESTION NO. P10292: Sony kpr53ex35 projection TV, after a warm up of around 1 minute, the red shifts all over screen, but the bottom right quadrant of screen is really bad, tends to fall off to the right and down. home.mindspring.com/~wa6ati/ then go down the page and look for Sony TSS logs QUESTION NO. P10248: Sony KPR53CX35 projection TV. Need to get into the service menu but all codes I have tried by remote do not work. Also checked back of TV for the small manual button that older Sony's sometimes have but this one does not have one. Try sitehome.mindspring.com/~wa6ati/Sonyid.pdf QUESTION NO. P1159: Sony KP53v15 projection TV does not turn on. When plugging in two clicks can be heard. There was one blown fuse on the convergence board. I replaced it but there is no change Replace convergence chips. Check for shorts and replace diodes for power supplies to convergence board QUESTION NO. P7109: Sony KP53XBR45 projection TV picture had severe intermittent vertical pincushion symptoms. Pincushion problem stopped and picture now exhibits good convergence in center, bad convergence at perimeter. Straight vertical picture lines are displayed as wavy lines horizontal scan lines look shifted relative to each other. Vertical compression, bottom 3" of picture missing. Fuses on convergence board OK. Have not replaced STK ICs yet The vertical drive signal was incorrect. This signal originates on the M board from IC3005 (CXA1477AS), the Luminance/Chroma/Sync (Y/C/J ) Signal Processor. Replaced this part and set now works fine QUESTION NO. P6141: KP46S15 projection TV, original problem was no picture or sound. Blown fuse on D board. Replaced both STK392 010 and both fuses which corrected the problem. New problem is double lettering on the left and right side of the screen in green and pink. The center of the screen is OK. Look at resistors mounted under the heat sinks that the STK's are mounted on. Bet several have opened or changed in value QUESTION NO. P4177: Sony KP53V15 projection TV has sound but no image. Check the convergence board for blown fuses or multiple broken solder connections, if the fuse(s) are blown you will have to replace them AND both STK`s on the convergence board, use SONY original parts or it will fail again QUESTION NO. P4268: Sony KP41T15 projection TV, when powered on, the picture did not come on and the timer/standby led keeps on flashing. If I keep it flashing for about 5 minutes, unplug the power from the electrical out let then plugged it back in immediately, the picture will come on after flashing exactly 10 flashes. I checked the power supply for any abnormal voltages that sent to the high voltage protection circuit to shut down, but everything looked normal. Sony has incorporated a self test circuit in their newer televisions, both direct view and projection. The indication that this circuit has found a failure is the STBY light blinking on the front of the TV. Call for a fax on how to troubleshoot this circuit 9005557669 for non authorized service centers QUESTION NO. P4139: Sony KP53XBR35 projection TV, the convergence is perfect in center of screen but the outer edges are all out of wack All three guns. Replaced two blown 3.15 fuses on the D board but no help. Anytime those fuses are bad you MUST replace both of the STK`s on the convergence board. Do not check, just replace them both at the same time (they are not cheap) QUESTION NO. P22610: Sony kp 53s35 projection TV, when first turned on timer standby light blinks off and on relay clicks off and on. When ant is disconnected the standby light goes off, and there is snow sound and a momentary flicker in the crts. Sometimes the sound will come and stay on with no picture After further troubleshooting, found vert IC, and IC protectors bad. Set worked find after replacing QUESTION NO. P549: Sony krp46ex20 projection TV has a convergence problem. The screen has red, blue and yellow shadowing. Tried to center picture and the r h and r v do not work resolder convergence ic's. if that does not work, change (STK xxxx) QUESTION NO. P585: Sony KP53S15 projection TV. Initially after turning on "power," I can hear it trying to perform some type of P.O.S.T. but within 2 seconds, it does not power on at all. The "Standby/Timer" light on front panel will blink once or twice and then it shuts off by itself. cannot find any blown components especially on the power module. Could not fin a power protection switch. I can hear some type of relay trying energize but cannot tell which one on the power module board Check convergence board for possible blown fuses QUESTION NO. P5263: Sony Kp61V15 projection TV. In Picture inPicture mode only, the color is not Synchronized (color bars rolling through). When swapping from PIP to main screen there is no color lock issue. So only the PIPtuner is involved. The color is Unlocked in PIP mode no matter which input source is selected (Antenna, video 1, 2,or 3) Since it affects the PIP when bypassing the PIP tuner than it obviously is not the tuner causing the lack of color sync. I would suspect something on the PIP sub assembly or bad smd caps. Specific to the pip circuit only after the tuner and if section QUESTION NO. P3271: Sony KPR53CX35 projection TV has no picture, has sound. There is no high voltage Replace jungle IC QUESTION NO. P2110: Sony Videoscope XBR KP53XBR35 projection TV had a blue convergence and pincushion problem. I found that the convergence chip IC1705 had a cold solder joint and resoldered it. The set worked fine for a couple of days then F902 blew. I replaced the fuse and it started working prefectly again. A couple of days later the TV powered itself off and stayed off. The power relay clicks once a couple of seconds after plugging the set in, but there is no response when trying to turn it on You need to replace both Ic`s, 1704 & 1705, check both fuses and the low ohm resistors to the convergence circuit. very common problem with those Sony`s I replaced both STK's and found two burnt out percision resistors and one blown fuse. It still does not power up. The 18V power supply is measuring 0.4V. Are there any conditions which have to be met before the 18V turns on, or is it a bad supply? The set will not power up because the +18v and/or the 18v power supplies are bad. These are located on the power supply board (G). This board is no longer available from Sony. For the +18v supply, check the halfwave rectfier D604 (D10SC6M). For the 18v supply, check halfwave rectifier D605 (D10SC6MR). Also check R604 for continuity. It is a combination .1 ohm, 1/2 watt resistor and fuse in one package QUESTION NO. P12131: Sony KPR 4110 projection TV has no picture but sound. Has graphics Open icps on convergence board. After changing check to see if conv. out ics are getting warm. If not, it is a bad ic QUESTION NO. P11235: Sony kp46v25 projection tv. Blown 601 fuse on D board. Disconnected red convergence plug from D board and replaced fuse. TV will work in this mode but red convergence is not working. If I disconnect blue convergence plug and connect red convergence wire, the red convergence can be adjusted using the blue on screen convergence controls. If I plug the red convergence plug back into its correct location the fuse will blow. I suspect one of the ICs (1601 or 1602) is bad on the D board. With the red plug disconnect Replace both STK output ics and associated fuse devices QUESTION NO. P10252: Sony kp53xbr35 projection TV. Convergence IC's (2 x STK4278L) replaced in June 1999 along with fuses. 18 and +18 volt supply appeared OK. Worked for a couple of months, now same problem. I received a reply in sci.electronic.repair that said the pins on the IC's have to be bent a certain way or the IC's will burn out again eventually. Does that make any sense? Both times the problem occurred was when the set was first turned on not after it had been in operation for awhile. I have service manual Be sure and apply heat sink compound to the back of the STK's. This will help, but it won't eliminate what is obviously the weak point in that set's design. The Stk4278L has the L on the end to denote the L bend in the pins, using a Stk4278 would necessitate bending the pins. I can't see how that would be a problem, if done with care QUESTION NO. P9279: Sony VPH1031q projection TV will not power the fans and gives a solid vertical line for a few seconds before shutting down Loss of vetical sweep and protect. Check the vertical output and supplies QUESTION NO. P9215: Sony KP61V15 projection TV had a pincushion and focus problem. Replacing STK's and fuses corrected the pincushion problem. Unit still has very very poor focus. Lenses do not appear to be dirty (I did clean them) and the focus control does change the focus but never gets near to correct Try moving yokes slightly forward or backwards, then retry focus controls. Experiment, it often works QUESTION NO. P9229: Need to know how to get into service menu to adjust convergence on a Sony Videoscope Rear Projection TV. (48" Model Less than 2 yrs old. Hard to get at back to see model#) On most newer Sony TV's, using the remote with set OFF Push DISPLAY(5)VOLLUME UPPOWER. That should get you in (be Very Careful) QUESTION NO. P981: Sony vph1020Q projection TV. When trying to power on it goes on, off, on, off, it will not stay on. It seems to have some kind of power supply problem OVP. May be shutting the unit down because it sensed abnormal parametres. May be regulator or leaky caps in supply. Try powering up @ reduced input voltage, may help further diagnose problem QUESTION NO. P9157: KP53v15 projection TV has sound but no picture. It only has two arched red lines about 1/3 down from the top of the screen Check the fuses on the convergence output pwb. If either one is open replace the STK output devices. Also, check for any ring or service cracks in the soldering of the other components on this pwb QUESTION NO. P7155: Sony VPH600QM projection TV. Just replaced from Sony 1040 CRT(suggested). Everything ok except when screen all white sky are white then all the pixels or image gone foge fuzzy, focus problem reduce bright and pic ok but picture not bright enough. Reduce video gain does not help. Is it just the way CRT works nothing I can do about? On the test pattern I can see the blue gun is more fat then other and that is best focus I can get It sounds like the projector you got has tired tubes. The controls are turned up to compensate but when the screen goes all white the adjustments cannot keep up. As for the blue being "fatter" this is standard. Every Sony VPH I has used requires the blue to be slightly out of focus for the right brightness QUESTION NO. P6184: KP46S55 projection TV. The picture intermittently narrows, with pincussion distortion. I changed the convergence Stk's Check the pin output transistor and associated capacitors. Usually the area around the transistor is discolored from excessive heating of the transistor. Also check the other active components in the pin ckts QUESTION NO. P6910: Sony VPH1272Q Front Projector. Need to know how to enter the Service Menu to adjust edge convergence/alignment You enter the service mode by holding down the "Test" button for about ten seconds, at which time you will be prompted on the screen to press the up arrow to enter service mode, and then finally you will need to press "Test" again. This allows you do adjust the fine convergence and all the geometry, as well as the bias and gain of the 3 guns. The Electonic focus and "Screen" controls are under the case in a black plastic grouping to the right of the keypad You need to hold down the test button for about 510 seconds. The projector will ask you if you want to enter the service main menu or something like that. I hope you have the service manual handy or experience in doing convergence setup. Because if you lack experience in this area you can get yourself in a lot of trouble and get the projector all out of whack QUESTION NO. P5184: KP46V15 Sony Projection TV. I have a yellow vertical band on the right side of screen, after adjusting the convergence the white cross has a little yellow on each side of the horizonal cross Check the coolant fluid for bacteria growth. Fluid should be clear, not cloudy. The contimination tends to be worse on the blue and green crts but also affects the red. The material tends to difuse the light coming thru it and can cause a similar effect as defocusing the lens. This may be exhibited as a display on screen that can be focused but appears larger than normal width wise. Similar problem as found in the Phillips proj tvs QUESTION NO. P5119: Sony VPH1270Q Projection TV, lost frequently its convergence after power off Check the convergence panel for possible solder cracks and for loose connections at the harness connectors QUESTION NO. P5111: Sony KP46V15 projection TV. When first turned on the picture is fine, after a 5 to 10 minute warmup the entire picture area will expand out most noticably in the corners causing a vertical line near the edges to look like it bends out at the corners. Also a convergence pattern will show the vertical center line to be as it should and the horizontal line shows a red shift to the right and a blue shift to the left. The picture will continue to pop into correct alignment and then again expand out at irregular intervals for the next 30 minitues to an hour when the picture will stabalized as a normal image. On a few occasions the overall picture will seem to darken slightly with a diffuse horizontal band of approximately 1/3 the heighth of the screen being more markedly dark Try the STKXXXX convergence outputs and check the convergence panel for crackes solder connections. Also check the Pin output transistor and associated circuitry QUESTION NO. P3236: Sony Rear Projection KPR4110. Video muted, sound good, sleep light comes on for 10 seconds. Can unmute video by removing mute 1 line on convergence board but it will not let me adjust convergence for red or blue. All voltages tested were good You have a failure in the vertical circuit QUESTION NO. P3196: KPR4110 Rear projection TV (Sony). No convergence adjustment for red or blue, the ones using the STK4121II. Everything else ok. Green OK. I have checked all obvious (fuses, voltages, solder joints) You did not say that you changed the stk devices, many times the prime suspect QUESTION NO. P2168: Sony projection TV. Blurry picture without convergence problems. After removing lenses from the tubes, I notice a smudgelike appearance on the face plates of the CRT's. These coolant chambers appear to be factory sealed. How can I open up the chambers and replace the fluid, it also appears that the grime in the chamber will need to be scrubbed off What you will need 1. New fluid 2. Denatured alchol 3. Some of those old fashion PIPECLEANERS, the long ones. (you can get them at a crafts store) What to do: 1. Remove the crt, and take off the lense assy. NOT THE SEALED ONE 2. Locate the fillhole, It is big flat phillips screw 3. Drain the fluid 4. Using the alchol and pipecleaners you can scrape the gung from the inside of the fixed lense 5. Rince well and let dry 6. Refill with new fluid. Reinstall the fill plug, and clean the crt If you were very carefull and did not disturb the yokes it should still be pretty close in alignment QUESTION NO. P2164: Sony KP53V15 rear projection TV. Sudden appearance of severe pincushion and color misalignment around the edges of the screen. The edges look like that are pulled in. Picture appears fine and aligned in the center of the screen. Reception and all colors are fine. The problem persisted since it appeared. Occasional flicker of the entire screen image Check the fuses on the convergence panel, also change the converergence output devices STKXXXX, then check the board throughly for ring cracks ar the regulators and controls. Been finding a lot of these lately; also may have a pincuahion output problem but suggest trying the convergence fixes first QUESTION NO. P1036: Sony Rear Projection TV Videoscope XBR model KP53XBR35. The convergence vertical line is fine, but the horizontal line extends red off the right side and blue off the left hand when the vertical line and center are set correctly. Nasty pin cushion on all four edges (center of each pulled in) and the rgb images are badly misaligned further out from the vertical center line of the TV. Corners are badly misaligned for colors, but not pulled in as badly as the center of the edges. I assume something went bad, but nothing obvious. Is is possible that it simply needs some kind of physical alignment of the guns? I had thought not since the center convergence is good, but I know not much about projection TV's Remove speaker grill to get to convergence board. There are two fuses on this board. Usually one of them is open. If one is open, you have a bad output IC. No way to tell which one. I would replace both of them and both fuses. I think they are IC1704 and IC1705, and fuses are F901 and F902. Do not touch any of the controls or anything on the picture tubes to try to repair this problem or you will make things worse IC1704 and IC1705 are no where to be found on the circuit board. However, there are two chips labeled IC904 and IC905 which are physically near F901 and F902. Can anyone verify if IC904 and IC905 are the chips actually referred to? Have exact same set. IC1704, 1705 are on right hand side of board. They are big and should say STK4278L on them. I had/have same problem. Replaced the IC's + simple voltmeter check of + and 18V supply and check for blown associated caps. No obvious problems. Now same thing has occurred 3 months later. Replacing IC's has again fixed problems but it seems obvious something else is going on. 18volt supply to IC's reads 18.8 when related fuse is pulled and 18.4 when installed. +18volt reads 18.2 (fuse out) and 17.9(fuse in). This (18v supply) could be the real problem but not sure yet. You can get new STK's from AudioLab in Georgia or B&D enterprises. They are both on the internet QUESTION NO. P92411: Sony Projector model # BPH1000Q. Symptom: Weak or dark picture, possible intermittent video Remove AVIO panel, located front right side of projector. Check for broken traces @ CJN202, Video input BNC connector. Connector ground also may need to be resoldered. Seems to be a common problem QUESTION NO. P7261: Blue gun on Sony Projection TV (KP46XBR25) after warmup has compressed sweep (sweeps from 23 inches on either side, therefore converges ok in center but off on both sides). Any ideas? Try the convergence output ics, change both red and blue. Also, may be a defective yoke, rare but I have seen a few in Sony. First I'd suspect the convergence ics Sony KPR46XBR & KPR53XBR plus similar chassis. Symptom: Severe Pincushion Cure: Replace 2SA3101 and 33ufd@160 v capacitor. Items located centre, rear of main chassis. Transistor on large heat sink, cap just to rear of same heat sink. 2SA3102 will also work. Note: Chassis area beneath the transistor may appear charred or discolored. The transistor will be shorted