Tv Rca J25220gg Tv With A Ctc167m Chassis Fel : The

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TV RCA J25220GG TV with a CTC167M chassis Fel : The color is fine and the picture quality is great but sometimes if you leave it on or turn it off then back on you get different colors in the middle of the screen with outlying areas maintaining perfect color in the program. This is an intermittent problem that freeze spray doesn't detect, nor does taping on the neck of the tube change anything. This problem cannnot be induced when the picture is good and we're unable to get it to go back to normal when the picture goes bad. Looks similar to a convergence problem with the different circles of color in the center of the tube but it has perfect color in all other areas outside of the effected area. Åtgärd : Due to the thermal type of problem you describe, I would think seriously about the possibility of a warped shaddow mask in picture tube. Some where this TV took a jold or manuf. defect. I cannot see your problem but there is also a degauss circuit that could cause this problem but condition would not change. ------------------------------------------------------------------------------------RCA TV chassis CTC169BG. Fel : I replaced HOT, Q4401 chopper transistor, CR4401, CR4402, C4401,C4402. When power button LED blinks on & off, and a vert. line blinks in middle of screen from left to right. After some time set will come on and play perfect, until turned off. Åtgärd : Believe your problem is connected to the "e" prom. This is a very busy slave. ----------------------------------------------------------------------------Sony KVM2130A TV Fel : when turned on, the picture is brightness and out of focus. All voltage of driver transformers is high ( B+=135 and it should be 119 v). Checked for bad cap, diode and resistore. I will replace str54041. I do not have a variac, can I build it? Åtgärd : Purchase a variac, do not attempt building one, safety and isolation problems in home brews. Try placing a 100 watt lamp in series with the B+ to the deflection. Probably the regulator is the problem. ----------------------------------------------------------------------------NEC CT-2505A TV Fel : with a vertical problem, retrace lines are visible at the top 3-4" of the screen. It seems that the top 1.5" of the screen is folded over on itself. Is this chassis the same as the CT-2610 as listed in the FAQ (similar problem)? That problem was resolved by replacing the tantalum caps in the vertical section. Åtgärd : Very good probablity. Same basic design and component usage. ----------------------------------------------------------------------------Sony kv-27xbr50 TV, Fel : after 15 minutes to 3 hours it shuts down. There is no set time thus making it hard to test. Åtgärd : Check for multiple inferrior solder connections in area of flyback and driver ckts. ----------------------------------------------------------------------------Sony kv 2781r TV. Fel :Replaced h-out trans and 135 volt reg ic. Worked for couple days then went down. Same components are bad. Replaced both, now set runs but there is a 60 cycle hum, the 135 volt supply willnot regulate. It runs at about 145 volts. I substituted the hot with a 40 watt lamp. The power supply still will not regulate. H-out gets very warm in a hurry. Is it a faulty 135 volt reg? Åtgärd : Check for mutiple solder connection faults at the flyback and driver transformers. Also for defective caps in the power supply, esp the small blue ones. ----------------------------------------------------------------------------Toshiba cf27c40 TV Fel : when turned, on the screen washes out (all white) then it goes into high voltage shutdown. Åtgärd : CRT drawing excessive current due either to a fault in the crt or more likely a problem in the G-2 bias level or video ckts. Remove the crt board and see if the set still shuts down. If it does not reduce the screen level, reconnect the pcb to the crt and check again. If the set goes bright with protect then suspect the video ckts. May also be the fbe, screen/focus supply device. ----------------------------------------------------------------------------Sears 19" Fel :I need replacement devices for a Sears 19" Vertical deflection surface mount devices which are mounted on a ceramic assembly. The device # B905 and D1220 which appears to be surface mount pwr transistors. Also need replacement for AO device small signal transistor which appears to be the driver(s). The total assembly has a JU0069 #M1 number on it. Åtgärd : I have tried to re-solder that module many times and it just keeps failing, the actual part # is not the JU0069 but most S/F parts distributors know what it is. If it is still available, the part number is 4090140707. Sounds similar to the regulator and vertical components that Hitachi used at one time. If so, these components are not available any longer. ----------------------------------------------------------------------------LXI 562.40812950 TV. Fel :Picture first started to grow/stretch vertically over about a month's time. Then suddenly horizontal black lines developed, picture stretched severely, and bright multi-colored horizontal line (like concentrated signal) at the bottom. Checked the main board, no heat marks, no apparent bad solder joints. Tried to change input from cable to A/V with VCR to by-pass tuner, no change. Adjusted "Height" adjustment, bright multi-colored line would disapear at bottom, but picture remained severely stretched. Åtgärd : Loss of regulation in deflection supplies. Similar to NAP sets in same time peroid. Check coolant fluid also. ----------------------------------------------------------------------------JVC C1950 TV Fel :came in with no power. Checked all components in the main supply found cr109 in power supply bad and replaced. Turned TV on have power to the screen and audio works but no picture. Åtgärd : May be out in left field but some of these, if my memory holds, had problems with the + 9 volt regulator. Seems that regulator feeda many areas. Also, check horiz drive pulses to the output and fbt areas. B++ to crt, etc. ----------------------------------------------------------------------------NEC PJ-4600EN(B) 1985 TV Fel : the picture does not come in clear, goes in and out. The sound also goes in and out. If I remove the video jack from the FIN2 block on the board labeled H07 4 57 the picture stabilizes but is not quite right. The higher the channel number the worse the reception. Also there is a strip of yellow across part of the top of the picture. Åtgärd : Loss of proper bias to tuner, video processor circuits. Failure of multiple electrolytics in supplies. Poor solder connections on the signal and power pcbs. Leakage of crt coolant onto the pcbs. NEC no longer supplies support for these devices and specific components, other than generic, are getting hard to find. BTW, how are the crts? If they are original they are probably in very poor shape. ----------------------------------------------------------------------------Sony KV21R1D TV Fel :picture and audio are ok. When I switch to Teletext-mode only the frame appears, but no Teletext-page. Is that a hardware-problem or only in the setup of the TV? Åtgärd : Probable hardware problem. Does the set work in the closed caption modes? Make sure that modes are properly set. CC/T-T decoder problem or distortion of data - signal coming in from source. ----------------------------------------------------------------------------Toshiba CF2034J TV. Fel :Replaced bad HOT and blown fuse, turn on power and deflection burns. When deflection yoke connection is removed, there is sound and dot on screen. Problem with deflection yoke or some other component associated with it? Åtgärd : Very good probability the yoke is shorting out. I have seen them get so hot that the neck of the crt cracks. Seems more common on the proj tvs than the direct view. ----------------------------------------------------------------------------RCA CTC176J2 chassis TV Fel :which will not fire when first plugged in. After 10-15 minutes it turns on. We checked the usual (tuner, eeprom). Åtgärd : You have loose ground connections. Remove bottom cover of tuner and solder around the frame & the solder stakes that come through the circuit board. Also solder the frame around the CPU and bandswitch i-c. ----------------------------------------------------------------------------Symphonic TVCR13F1 TV/VCR. Fel : The remote control will not control the functions. All function buttons on the set itself work properly. The remote is putting out a good signal at all times on all functions because I tested it with an infrared card tester. Occasionally, and I do mean very occasionally, the power comes on using the remote control. Åtgärd : Check the solder connections at the base of the remote rcvr mod. I have found several loose, causing erratic operation. ----------------------------------------------------------------------------RCA chassis CTC169AS, 32" TV Fel :, tube seems to be weak on red gun. As contrast is turned up, the red color starts to smear in picture extending past outline of objects, blue and green colors ok. I suspect the tube being bad as it is a 1992 model, but not sure. Is this a board problem or a tube going bad. Also where could I locate a price for this tube? Åtgärd : Switch the red and blue or green inputs to the red gun. This will tell you if you have a picture tube problem. If the problem switches to the other gun, the tube is ok. ----------------------------------------------------------------------------RCA CTC185AA TV Fel : with no menu on screen. I replaced EEPROM 223181(from RCA dealer) and made good ground connection in tuner section. Now TV on OK with on screen menu, but after I did auto search channel, channel will not change. Also, when I changed color (on menu) the vertical size of picture also changed. I replaced almost five EEPROMs already. Åtgärd : Solder grounds around tuner frame & shield stakes that come through circuit board. Also solder frame around CPU & bandswitch i-c. If this does not solve the problem, the CPU is not writing the info to the eeprom. ----------------------------------------------------------------------------RCA ctc 156 TV Fel :extreme brightness, no retrace lines, no control over brightness. Boost voltage good, all video signal scopes out good. Åtgärd : Check R4701 10~, C4703 47uf/250v, CR4701&02 on 200v line. Check video buffer transistor. ----------------------------------------------------------------------------Magnavox RF4800AK02 TV Fel : had bad vertical deflection. I traced the problem to a bad resistor (R420, 1/8 watt) next to the power transformer. The 3rd band is damaged so I am not sure what the ohmage should be. The first two bands are brown/black and then it appears to be either brown or black. I replaced it with a 10 ohm resistor and everything works OK. I would like to confirm that this is the correct size. Åtgärd : Value of R420 is 1~ 1/3w. The 10~ will probably last a long time, as there is not much current draw in this circuit. R420 is listed in Mag. Man. 7412 as a 1 (one) ohm 1/3 watt resistor. This usually opens when Vert IC 331 is bad. (Old IC P/N 6124440001) (New IC P/N 483520917162). ----------------------------------------------------------------------------MGA cs-2193vc TV, Fel :when it is cold some channels are ok, some do not work, some pop in and out. After about 45 min to 1 hour the set works fine or after it is on for 2 minutes and I unplug it and plug it in and turn it on it sometimes works. Åtgärd : Tap on the tuner. If symptom clears, pull tuner & solder ground connections on the trace side of the board. Be sure and use an iron hot enough to solder to the turner case, usually a 35w. Remove tuner open up and look at posts and other areas for ring cracks. Solder suspect areas and reinstall tuner. If it fails again, check tuning voltages. If there is still trouble, replace tuner. ----------------------------------------------------------------------------GE ctc158aa3 TV, Fel :picture and sound working fine. Character display is wrong. Some characters become color block or underscores. When pressing channel up key, the channel is changed correctly, but the display of channel number goes like this 11, 11, 13, 13, 15, 15. Åtgärd : Remove tuner and resolder ground connections on board side of tuner, around the edges and also metal shields that pass thru the board. ----------------------------------------------------------------------------Sony KV32XBR95S TV Fel :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 1195-065 for the board, and the board has both 1195-054 and 1195-045 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. Åtgärd : 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. ----------------------------------------------------------------------------RCA CTC140 TV Fel : blank light grey screen comes on but no audio/video. The screen menus and channel display still displays. Same result using all inputs. Åtgärd : Try resoldering all 3 legs of q2300 the if amp transistor and usually pins 1-8 of u2300 the IF ic. This usually takes awhile because there are sometimes a lot of poor joints in that area of the board, look it over very carefully it usually fixes these sets. ----------------------------------------------------------------------------Sony KV27TS27 TV. Fel :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 them 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? Åtgärd : Check T-604 and R607 a .1 ohm 1/2 watt (goes way up in value). ----------------------------------------------------------------------------Hitachi CT2250B TV Fel :is dead. Clicks when powered up. I heard that this unit has a problem with a capacitor in power supply. Åtgärd : You heard right, check/replace C840 and C841, usually 840 is the bad guy the original is 330uf @16 volts. I use a 330uf at 25 volts, they hold up better. ----------------------------------------------------------------------------RCA CTC 187BD2 TV Fel :has a slight afterglow problem on CRT after power down. It is light green in color and looks similar to a sidways bowtie above center on the CRT. Recent failure of horizontal output transistor and EEPROM. Aligments complete after their replacement but this afterglow problem still persists. Åtgärd : Afterglow in Rca`s sets is normal! This is easily confirmed by calling Thompson if your customer does not believe you. They will tell you the longer it stays on the screen after shutdown the better your picture tube is ----------------------------------------------------------------------------Electrohome 79CH01 TV (made by Mitsubishi) Fel :. I need a source for discontinued flyback part # 334P16808 as it has a hole in the side of it. Åtgärd : Try CRC components, they list it in their flyer but it says call for price the # is 1-800822-1272 ----------------------------------------------------------------------------Proscan P46130WK TV and chassis CTC169PXA. Fel :Initially there was intermittant reception on channels above 36, then it went dead on him. I replaced the typically bad CR4118, CR4108, and U4101. Now the power supply works, but at turn on, the unit shuts down instantaneously. B+ only gets to about 60 volts before it shuts down. The HOT and all surrounding components test good. The Xray prot. input of the micro is at normal level, and none of the supplies coming off the flyback are shorted out. Åtgärd : Try pulling the anode lead (from the flyback transformer) out of the HV divider block, lay it inside a coffee cup or other non metallic container and then turn the set on. if the set comes up and stays up the HV divider block is bad. ----------------------------------------------------------------------------RCA ctc 169ccs TV Fel :does not power up at all. The fuse is ok. There is misc voltages across the board but I have no schematic to verify any voltages. I checked diodes in power supply and they seem good. Åtgärd : You will probably never fix this chassis without the service manual, there are probably 20-25 known causes for this set being dead.HV divider block, cr 4118, c 4401, c4402, cr4401, cr4402, cr4101, R 4317 etc. etc. etc. get the manual or if your not a qualified tv tech do yourself a favor and bring it to one. ----------------------------------------------------------------------------Zenith 21" Fel :that has no other identifier that I can find. There is a straight horizontal line across the middle of the screen so I know that I have to replace the vertical section. However, there is no label on anything so I do not know where to find the vertical section. I do not know how you are going to help without the model number. Åtgärd : Face the rear of the set and describe the layout of the circuit board/boards. One large board/two boards/three boards, location of the high voltage transformer/ right/left/center etc. Are boards horz or vertical? Look for dates on the components/picture tube/inside the cabinet. Sometimes there is a sticker inside the cabinet, giving the circuit board pt numbers. With this description, someone will recognize the set and be able to help. ----------------------------------------------------------------------------ctc185ab TV Fel :with a vertical problem. I checked the vertical circuit . It seemed to check ok. The vertical was not filled out at the top about 1'' short. I changed the eeprom. Then went into the factory settings. I do not have a schematic so I had to guess at them. I finally got the vertical to fill back out at the top. But when I tried to get back out of the menu. It popped back down 1'' again. It does this every time I try to set it up. Is there more to the procedure that I am not aware of, or do I still have a problem in the vertical circuit? Åtgärd : Make sure you are using the proper eeprom, for U3101, as they all look the same, with the same # printed on the i-c, sometimes with a paint stripe across the #. Call up the service menu and record the data for each service position. Then turn off set and install an eight pin socket. Install the new eeprom pt# 233181. Turn the set on and program the new eeprom with the data recorded from the old eeprom. Check operation of new eeprom by calling up customer menu and adjusting the controls. Turn set off and unplug. Let set for 1015 min. Plug in and try all functions. If information to new eeprom won't stay, you will have to replace the CPU #233180. ----------------------------------------------------------------------------Toshiba CF2665K - TAC 9000 TV Fel :, the picture goes black to a thin horizontal line in the middle of the screen. The sound is fine. Åtgärd : Most likely C301 and C305 are bad, they are usually 1uf @ 50volt. Some chassis`s are 2.2uf@ 50volt. All of these 25-27`` sets use these caps. They are usually red or brown in color ( different color from the others). Problems in pincushion output, correction, and driver circuits. Check for overheated components and changed value resistors and electrolytics. ----------------------------------------------------------------------------CTC187 TV Fel : with no voltage on Eeprom P-6. Cannot find the source of this 4.8 v. Changed U1001, U3001, Eeprom, traced all solder connection on replaced IC's, traced this circuit from Eeprom to all IC's connected, including Tuner, Stereo Decoder, PIP IC. There is no short on the line, hokds 4.9 v from external source. I had thought it might have fed thru an IC but it does not. Åtgärd : Had same problem and found crystal on u1001 not working properly. Check and make sure that this crystal is oscillating or u1001 will not feed this voltage. ----------------------------------------------------------------------------RCA F19201BK TV, Chassis CTC175C Fel : with weak sound. At full volume it is at about normal listening level. I checked the speaker, two transistors and all the diodes in the audio section. Åtgärd : ctc 175 and other families had common problems with bad connections in tuner, also corrupted the E-prom. Would see different problems and also low audio as you are describing. Two choices, can either replace the eprom and restore normal values or unsolder pin 8 of the E-prom and plug unit in. Use the end of small screw driver to short pin 8 to the pad and power unit on. Once the unit powers up, remove the screw driver. Then push menu button to go to the menu for the speaker control. You will notice that the speakers will be turned off. Once again take your screwdriver and touch pin 8 to the pad while you select to turn the speakers to the on position. Normal volume should return. With pin 8 still to the pad turn the set off -this will allow for the micro to store the info to the e-eprom. With pin 8 still to the pad turn the set back on -normal volume should return--if so turn set off unplug unit and resolder pin 8. ----------------------------------------------------------------------------Sony KV-2781R TV Fel : 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. Åtgärd : There is a .47uf cap in the horizontal drive circuit (on the base of driver?) that can cause this problem. ----------------------------------------------------------------------------Magnavox 19L4 series TV chassis Fel :. Set dead. Checked voltages at IC430 130 regulator suppose to be 159v in and 130v out. I get 160v in and 167v out. Changed the ic430 regulator, no change on voltage readings. Åtgärd : This set is infamous for R502 going way up in value causing dead set symptoms, value is 47k 1/2 watt ----------------------------------------------------------------------------Phillips TV 2b chassis Fel : picture is overlayed with rippley bars similar to sound bars. The problem is worse with stronger stations. Checked voltages, appear normal. I suspect maybe a leaky cap. Åtgärd : Probably, the tuner AGC does not work. Check the AGC voltage, should be ca 8V with no signal, goes lower at a strong signal. Another possibility is oscillations in the tuner or IF amp, check screens, solder joints and decoupling caps in the IF; remove tuner and inject IF signal from a pattern generator to see if the tuner is at fault. Third, it may be interference from some clock oscillator for the microcontroller, teletext module, nicam decoder or so. Check ground connections, decoupling caps, screens etc. Try removing "unnecessary" modules or stop the oscillators by removing crystals/resonators to find the fault. ----------------------------------------------------------------------------Citizen JCTV3403 TV, Fel : C3201 blew and I cannot read the value. Åtgärd : Capacitor C3201 is a 1mf 160v electrolytic capacitor. ----------------------------------------------------------------------------Magnavox TV 25G1 chassis Fel : will not start up. Have replaced regulator chip and FET in the switch mode power supply. Disconnected diodes in secondary of smps transformer. Cannot find any shorts or open resistors. Standby voltage of 12v and 5 volts is working. Åtgärd : Unsolder pin 18 of IC350. If set now comes on, replace the IC. I have seen this one on 25G1`s & 27G1`s ----------------------------------------------------------------------------RCA ctc 187 TV Fel :with the classic buzz. HO was shorted and I replaced it. Running the set at 90 volts the xsistor was getting rather warm. I replaced regulator, driver transistor & cap, also yoke caps & still have the same problem. Also, when the set is cold pix and sound normal but after 5 min or so pix starts pulling in from the sides. I suspect a pincushion problem but I do not have the prints to pin it down. Åtgärd : Check the pincushion diode. If it is ok, resolder it. ----------------------------------------------------------------------------Zenith SR2552S TV. Fel :Vertical defl chip (IC2100) is cracked and broken. I cannot read the numbers. Åtgärd : The vertical output number you are seeking is LA7838. The nte cross is NTE7039. ----------------------------------------------------------------------------GE TV Chassis CTC175 Series, Fel : DEAD. No power from front buttons or remote. Jumped degauss relay to force TV to degauss or turn on, relay clicked, and blew AC line rectifier Diode numbered CR4004. Possibly blew transformer. Åtgärd : Solder all your tuner ground. If it is still not working try the eeprom (8 pins IC) U3201. ----------------------------------------------------------------------------Sony KV 27 TS 27 TV Fel :. 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. Åtgärd : More than likely R607 a .1ohm 1/2 watt res. is open. Also check q603. ----------------------------------------------------------------------------Toshiba 29" Digital 100H model 2999UXE TV . Fel : The picture in the top of the screen and the bottom have a bow. Service menu adjust did not help. Åtgärd : Might want to play with the yoke position and wedge insertions beneth the yoke. However, you may compromise the convergence adjustments. I do not think these chassis have dynamic pin correction for t/b of pix ----------------------------------------------------------------------------Toshiba CF30C50 TV (Chassis 9301). Fel :Sound is crackle only 99% of the time. Speakers appear ok, add on speakers do the same thing. Åtgärd : Change the MTS, assembly should say MVUS##? on the tag attached. ----------------------------------------------------------------------------RCA TV CTC169L chassis. Fel : I need a replacement transistor for Q2906 locator #ctc168/169L series chassis # on transistor is 3474. Åtgärd : Video buffer may require a ECG123A or similar. Comfirm base or use the original RCA device. I use a general transistor salvaged from another device but first confirm the base and type {npn/pnp }. ----------------------------------------------------------------------------NEC CT-2610A TV Fel :with a vertical problem, retrace lines are visible at the top of the screen. I jumped or replaced all electrolytic caps in the vertical circuit. Åtgärd : Replace, do not jump, the two tantalum caps in the vertical circuit with the correct values. ----------------------------------------------------------------------------- Sony KV-20TS27 TV. Fel :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? Åtgärd : 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. ----------------------------------------------------------------------------Toshiba cf2665k TV Fel :cuts off after a minute or less. The b+ is supposed to be 115v but is 117v. I did not think this to be a problem but the B+ regulator collector will increase to 70v and this is when the set cuts off. According to Sams this voltage should be 5 volts. I have also defeated the fails safe. When the set cuts off the b+ is never above 117v. The set will play forever at 95v ac in. Åtgärd : The problem was the yoke as it was arcing at 115v B+ yet at 90-95v would not. ----------------------------------------------------------------------------Sony Trinitron KV-32TS36 TV Fel :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. Åtgärd : Suggest replacing the component that you are resoldering, throughly clean the leads and solder pads before installing it. ----------------------------------------------------------------------------GE TV CTC175C chassis. Fel :Replaced and reprogrammed EEPROM, resoldered tuner grounds. TV will now turn on, but will not even try to scan for a channel. You select channels and get only snow, even on cable hookup. Åtgärd : Check for errors in the soldering, or solder splashes or fingers within the tuner. ----------------------------------------------------------------------------Sony KV 27TS27 TV Fel :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? Åtgärd : 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? ----------------------------------------------------------------------------RCA 25'' TV ctc177af or model# F25251WN. Fel :I have to replace the whole board somebody damaged it beyond repair. I am not Authorized to repair RCA TV's will I have a problem getting this board. I tried PTS and they don't sell this board. Where can I purchase this board? Åtgärd : Directly from RCA via an authorized service location, if it is still available. ----------------------------------------------------------------------------Fisher PC-8326 TV Fel :with a power supply problem. I thought the power supply was being loaded down so I connected a 40W lamp across 130V voltage read about 40V. Problem used to be intermittent now it is dead with 40V. Checked C7 main filter and opto-isolator D5. Do I have a bad regulator if so how do I bypass or test and where can I get the part. What is the part #? Åtgärd : This set is at least 14 years old, you may try Sanyo/Fisher corp for the reg ic but I'll bet it is nla. Many bad solder conections on the chassis and p/s. ----------------------------------------------------------------------------Mitsubishi cs3505r TV board # 930b38001 Fel :I need to know where I can get an obsolete circuit board for a Mitsubishi cs3505r TV board # 930b38001. Old board is broken in half and beyond repair. New board is no longer available. Åtgärd : Try Gibson's TV/Video Service @ 810-774-9730. Ask for David, we do a lot of MGA sets and may have a viable board. ----------------------------------------------------------------------------Samsung TXE2746 TV Fel :does not have full vertical deflection. How do I get into the service menu to access these parameters? I changed the vertical output ic and checked all caps in the vertical and power supply circuits. Åtgärd : With set off and using remote, press mute-1-8-2-power on. This will get you to factory mode. Then use the vol up/down and ch up/down to select parameter. For vertical height select va. Make sure you also check r417, r410, d404, dz303 and dz305. ----------------------------------------------------------------------------Zenith sls2504 TV Fel :will not power up. The customer thought he would repair it himself. After blowing several fuses, he soldered a wire across the fuse holder frying q3431, r3433 & rx3434. Now a cannot determine what to put back. Åtgärd : Tell the customer he needs the complete circuit module and order one from the Zenith Parts dist near you. Also, no warranty if he goes into this set again! ----------------------------------------------------------------------------Sony kv27ts27 TV Fel :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). Åtgärd : Look for small green circuit board labeled sbx1637-xx. Probably has leaky capacitors. DO NOT attempt to repair, just replace. Available as generic from several suppliers for reasonable price. ----------------------------------------------------------------------------Sony KX2501 TV . Fel : 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). Åtgärd : C1902 is a 330pf @2kv capacitor. Sony p/n is 1-102-327-00. ----------------------------------------------------------------------------Zenith TV SR3587DT chassis, Fel :looking for cross for video driver transistors labelled C5147 (Q501 to Q503) located on 9-1298-6 board. There does not seem to be an ECG cross. Åtgärd : 2SC5147 itself is listed in stock by MCM (800-543-4330; www.mcmelectronics.com); MCM also lists two similar transistors, 2SC4075 and 2SC4544. If insulating hardware is added, an NTE/ECG 376 will also be similar to 2SC5147. ----------------------------------------------------------------------------Sony KV-M14U TV. Fel : 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! ;( Åtgärd : 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. ----------------------------------------------------------------------------Sylvania RKX185 BK01 TV Fel :when the channel is changed, it will not lock on to the new channel until after some time, it will flash about 4 times then will select the new channel. I have replaced the tuner, no change. Åtgärd : Try adjusting the AFT pot. It is near the tuner. Turn it just a little at a time and change channels to see the effect. It usually only takes a few minutes to have it in good shape. This is a very common problem with these sets. ----------------------------------------------------------------------------Zenith Z25A11S TV. Fel :I need a source for module # 9-1790. Åtgärd : From Zenith Parts Department, these boards are now designed to be component level serviced. ----------------------------------------------------------------------------GE 31GT658 TV chassis #CTC187CK Fel :intermittently will not power on or off, also has int. vertical problem and gets fuzzy. I replaced vertical IC and all surrounding caps. Could this be IC U3101V? Is this considered the eeprom in this set and if so where can I find it? How do you enter the service mode on this set? Åtgärd : Menu, power, volume up, press power then volume up while still pressing Menu button on front panel of set. Typical Thompson On Board Tuner solder connections problem. If you are not familiar with doing this repair and the reference points at the mpu shield then pay a professional. Be aware, the changing of the parameters within the setup service menu can cause the set to go into protect mode. Sounds like the grounds on the tuner and microprocessor (IC# U3101) need resoldering. The Eeprom is IC# U3201 (RCA p/n# 223954 from MCM). Go to this website plop.phys.cwru.edu/repairfaq/REPAIR/F_rcatune.html to see details on doing the resoldering, and on the Service Menu information. ----------------------------------------------------------------------------Daewoo DPBS208GU TV Fel :with no supply voltages (dead) since antenna shorted. No fusible component blown. Switching transistor type #KSC5021F-R (mfr # TKSC5021FR) in supply section looks bad. Any cross reference? Åtgärd : Samsung's KSC5021F-R is 800 Vcbo, 500 Vceo, 5 Amp, 40 Watt, 15 MHz, Ton <0.5usec, Tstg <3usec, Tf <0.3usec, Cob = 80pF, gain = 15-30. Samsung has sold their power semiconductor line to Fairchild, so now Fairchild is the OEM source. For a cross, try 2SC3750, available from MCM (800-543-4330; www.mcmelectronics.com) or B&D (800458-6053; www.bdent.com), among others. Or you could try an NTE/ECG 2337. ----------------------------------------------------------------------------Mitsubishi CS-20203 TV. Fel : Thin horizontal line runs across screen only, sound ok. Åtgärd : Vertical output and associated diode, also may have opened fuse resistor in supply source ----------------------------------------------------------------------------RCA TV CTC187BD and CTC175A Fel : Where can I find EEPROM preprogrammed for RCA TV CTC187BD and CTC175A? Åtgärd : MCM Electronics (800-543-4330; www.mcmelectronics.com) carries RCA Eeproms, p/n# 225688 for CTC187BD and p/n# 217321 for CTC175A. ----------------------------------------------------------------------------Sharp CF25M4 TV, Fel : the horiz. output transistor failed after 15 seconds or 2 days of operation. I looked for bad soldered joints but find nothing. Åtgärd : Flyback, crt, horiz deflection, B+ to high,? Arcing noise present? ----------------------------------------------------------------------------JVC c-s2180m TV Fel :has only a horizontal line. All the components seem to be perfect. Åtgärd : Perfect one line picture? Then the parts in the vertical can't be perfect. Check output devices & sources. ----------------------------------------------------------------------------RCA T19060 TV Fel :will not turn on. When the power button is pressed the led blinks but nothing else happens. All the voltages on the switch mode board are at the connectors except 13 volts which feeds the on/off relay. I suspect this voltage should come from the deflection/power supply board but the schematic is very poor. Åtgärd : Standby voltages must be available any time the set is plugged in to source. The voltages at the relay coil should be there, otherwise the set will not even attempt to switch on. This voltage comes from the main supply ----------------------------------------------------------------------------Emerson TS-2587D TV Fel : is bright yellow when first turned on. Picture restores when channel is changed. No other symptoms. Åtgärd : Suspect broken or cracked connections in the video output section or on the crt drive board. Even poor connections right at the crt socket may cause such strange symptoms. It even may be a data problem but doubtful ----------------------------------------------------------------------------Sony 27XBR10 TV. Fel : B+ is down to 4 volts. There is no HV, and there is a loud, high-pitched 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. Åtgärd : 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. ----------------------------------------------------------------------------Supra Television Fel :I require the pin-out configuration for a Matsushita/Panasonic AN5265 IC. It is the audio output IC in a Supra Television. Audio in is ok, no audio out. Åtgärd : The pinout of the AN5265 Audio IC is pin#1, Supply Voltage#1 (12 VDC typ.); #2, Sound Input; #3, Mute (0 - 7 VDC, operates at >2.5 VDC); #4, Volume adjustment (0-12 VDC); #5, Filter cap; #6, Feedback; #7, Ground; #8, Sound output; #9, Supply voltage#2 (18 VDC typ.). I suggest checking the two supplies, and the voltages on the mute & volume adjustment pins. Subs to ECG-1789, same pinout. ----------------------------------------------------------------------------Symphonic TVCR19E1 TV/VCR. Was dead. Power supply works until powered on then clicks off. I replaced the 6 volt regulator to get it up thus far. Voltages are squirrely at the optisolator IC. IC601 and not sure, without start replacing components I have my 12v, 33v, 5v, and 6v. Åtgärd : Replaced capacitor c1026 470Uf@10v. ----------------------------------------------------------------------------Zenith SLV1340S TV/VCR Fel :. Was informed unit has Sears PCB's. Unit will not come on, and main fuse does not blow. I need an identity or a cross for Q02 (212 is number on component) located on main tv power pcb. Has d, g, s printed on pcb where component goes. Maybe a FET? Åtgärd : Q1002 is a FET and is listed as either a 2SK212E OR 2SK212F. Part # is 2SK212EZ or 2SK212FZ (taken from Zenith parts list). ----------------------------------------------------------------------------GE 09GP107 9" TV chassis TX82MB Fel :destroys H.O.T. in about 10 seconds. Power supply is not damaged but AC fuse does blow. Åtgärd : Flyback, shorted CRT, defective yoke, defective yoke retrun capacitor, excessive B+. On a 9" TV, how far do you really want to go? Check capacitors in h.o.t. circuit, you should find one open. ----------------------------------------------------------------------------Magnavox PR1902C127 TV is completely dead. There are no blown fuses (including the ones soldered to the pcb). Fel :I did replace one small transistor (cbc368), but can't find any other components that are bad. When the unit is plugged in, it makes no noise at all. If the power button is pressed, the LED flashes a few times and stops. Åtgärd : More than likely the vert. IC is bad along with a few parts in the Vcc line for it going back to the flyback. ----------------------------------------------------------------------------GE 20GT324Jx1 TV, chassis CTC175A. Fel :I changed the eeprom (dead set) and right now it works. But I have to set the horizontal freq. I tried to go in service mode (technician mode) by pressing power menu and Vol + and it did not work. Åtgärd : To access service menu press and hold MENU, then press POWER then VOL +. Use VOL + to get the value lever to 76. Press CH +. You shound see a scrambled pic. Adjust value for a slightly rolling pic. Be sure to check the tuner wrap for poor ground that probably caused the bad EEPROM. ----------------------------------------------------------------------------GE 25GT503 TV chassis # ctc177aa3 Fel :Need a value for cr 4704 & r4517 in a GE 25GT503 TV chassis # ctc177aa3. Åtgärd : CR4704 is RCA part no. 207878, no ECG replacement. R4517 is usually a 22 ohm, 1 watt. The Sams schematic for this chassis calls for a 30 ohm, 1 watt, but most chassis' we have run across use the 22 ohm ----------------------------------------------------------------------------Zentih SJ1325W TV Fel :has a high pitched squeal when plugged it. The H.O.T. appears to be ok, but not sure. Does this H.O.T. have the damper built in? Suspect the flyback. Åtgärd : Order the whole module but be sure the CRT is good first. Many of these sets have defective crts. ----------------------------------------------------------------------------Mitsubishi cs-2013r TV Fel :only has a horizonal line in the center of the crt. I replaced the vertical deflection ic and no change. Åtgärd : Check the supplies to the vertical ic, yoke, and return lines and components, espec any capacitors. Also the PCC circuit may cause problems but not normally total loss of sweep. ----------------------------------------------------------------------------RCA CTC185AB-3 TV Fel : does not turn on. I tested an EEPROM from other models but it does not work. For example, I tested the 177 and 175 EEPROM Model, cause the EEPROM for this equipment is not available. Åtgärd : The CTC 185 must atain standby mode, that is, with + 5 at the mpu and Eprom to allow access the info via Chipper Checker. Applying external supply to these items will allow communication and diagnostics. BTW make sure the version of Chipper Checker supports the newer Thompson Chassis. This CTC-185 chassis has 1/4 watt 1.5meg ohm near the degauss relay that occasionally goes out.The precise location would be at the rear of the hybrid voltage regulator near a large electrolytic cap. Pull one end out and check the resistance. That usually cures the problem. The color banding is brown-green-green/gold. ----------------------------------------------------------------------------Sharp SV - 6689X TV Fel :I need a CRT Output IC TDA 8153 for a Sharp SV - 6689X TV manufactured in Spain. I cannot buy this component in Australia and I have searched questlink.com and have not been able to locate this chip. Åtgärd : You might try VAAG Electronica HS in Spain (email, [email protected]), their website (www.vaag.es) lists TDA8153, showing 3000+ available at $23.60(US). TDA8153 is also listed on Techsonic's webpage at members.tripod.com/~techsonic5/html. Their email is [email protected], but they state a $50 minimum order, so you might wish to check on-line first, if they have any other components you need. ----------------------------------------------------------------------------Samsung 27" CT-3861CA TV. Fel :No picture, single thin horizontal line across center os screen. Audio and channel switching ok. Åtgärd : Change the vertical output ic and check the supplies. ----------------------------------------------------------------------------Zenith SG2589Y TV Fel :vertical picture squashed and approximately 2-21/2 inches raised from bottom of screen. Vertical pot just stretches picture. Åtgärd : Find the little white tag and order a rebuilt module. 9-XXXX-XX It is not necessary to replace the entire circuit for a vertical sweep problem. Locate the vertical i-c and change any electrolytic capacitors in the same area of the vertical i-c with the same prefix # ie vert i-c 501, replace cap c503, c504 etc. There will also be a main power supply capacitor located near the high voltage transformer, it will also have the same prefix # as the i-c if it is for the vertical circuit. ----------------------------------------------------------------------------Aiwa TV Fel : with blurred picture with abnormal color apppear on the screen. I check the flyback supply with level 200V but without output. Also perform the adjustment focus adjustment knob of flyback and also adjusted the red, green and blue potentiometer for correct fine tuning of colors on the screen. The result still blurred color picture. Åtgärd : Defective crt or focus supply to crt. ----------------------------------------------------------------------------RCA F20570WN TV, Fel :Chassis CTC166CS. Separate tuner module acts like on-board tuners of CTC 176/177 chassis. Channels 1-6, 14-17, 25-125 seem to work ok. But channels 7-13 and 18-24 lose sync, video, have microphonic type squeals, etc. Problem seems to involve antenna "F" connector of TV. Pushing/moving tight cable connection restores problematic channels, for a few minutes. New cable does not make a difference. The TV, of course, is set for CATV! Is this model chassis prone to this problem (bad soldering in discrete tuner module)? Åtgärd : Bingo! Replace the tuner module or attempt resoldering the multiple grounds and other connections. Requires removing from pcb and a good mag glass. Watch for solder spashes and excessive rosin flow. ----------------------------------------------------------------------------Philips 26CE1991 color TV Fel :with a focus problem. The circuit I purchaced has no voltage markings shown. I measured the HT as 30k volts and the Focus at 10k volts. A crosshatch picture looks quite normal except for being out of focus. Adjusting the focus control tends to make the focus spark gap arc on the tube. Åtgärd : Failure in the focus/G2 devicer circuit/ FBT. Nominal Potential should not be enough to jump the spark gap unless excessive humidity, dust, or a carbon track there is present. ----------------------------------------------------------------------------Sony KV-27HSR10 TV. Fel :The horiz freg is to high. I replaced ic301, the onle voltage off is on pin 30 of ic301. It is 3.9v instead of 3.0v. Incoming hori sync pulse are clean. Åtgärd : 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. ----------------------------------------------------------------------------Toshiba CF2040J 19" TV. Fel :The vertical sweep slowly failed over the course of a year, resulting in a picture that is completely blank at the bottom half of the screen. Åtgärd : Toshiba chassis' have the same problem. Replace C301. ----------------------------------------------------------------------------Phillips TV Chassis # 19A800-7561. Fel :Lightning struck the TV and it has no power. I cannot find any bad fusable resistors and the main fuse is ok. I replaced Q7518 and all the switching Diodes with no change. Åtgärd : Check for blown circuit traces (mostly ground traces). ----------------------------------------------------------------------------Grundig T55-549 cuc5302 TV Fel :I need data service mode for Grundig T55-549 cuc5302 TV. Åtgärd : If this set has a service-mode field (4 digit code) in the OSD, try 8500 as the code (common for most Grundig sets). ----------------------------------------------------------------------------Sharp Chas # 21N21-DN TV Fel :has a Vert line and I believe the vert IC501 part # X0355CE to be bad but I cannot cross the part to anything. Is there a different prefix I should use to cross Sharp parts? Åtgärd : The entire Sharp part number is RH-IX0355CEZZ for that IC. I do trust that (to you) "Vert line" means a line extending left to right across the middle of the screen, for that is what is seen, when a Vertical IC is not driving the vertical yoke. ----------------------------------------------------------------------------Toshiba CF2628 TV Fel :would not turn on. I eventually performed repairs that brought it up. It now has a very dark screen that is not affected by the brightness or contrast controls. Åtgärd : Confirm proper G2 and focus settings and voltages. Proper drive voltages to output devices and at cathodes of crt? ----------------------------------------------------------------------------RCA F19201BK TV Fel :has a red picture. Swapping the red and blue gun supplies results in a blue picture. What are the commands to enter the service/calibration mode? I have replaced the control IC LA 7610. Åtgärd : Newer RCA/GE press volume + and Power @ same time, release power & press channel +. ----------------------------------------------------------------------------GE/Thomson ctc187cn2 TV. Fel : Upon plug-in, a whine is emitting from the flyback and unit does not power up. Even when crt is unplugged the whine is present. Åtgärd : Overload somewhere in the loads can cause the PS to run off freq and squeal. Check for excessive drains from supplies. ----------------------------------------------------------------------------Magnovox rj5540 ak01 TV Fel :has what seems to be sound bars in the picture and sounds like a jacobs latter. I replaced the horzontial trans. but did not help. The shop before me replaced it and it worked for a while. Åtgärd : The service literature for that set says not to replace the flyback, because it is factory adjusted to the board. Maybe thats your problem. ----------------------------------------------------------------------------Emerson tc2555da TV, Fel : h/o & reg ic last only 10 minutes then short out. Åtgärd : Check cap C435 = 1 uF/200V, the horizontal drive transformer and also its solder, and the FBT. Check the resistors off the regulator IC (R503, R507, R521). If the tube is CRT#A63ADG27X, check if it is arcing, which will blow the HOT & regulator IC, etc. ----------------------------------------------------------------------------JVC AV32730 TV Fel :has no picture and no sound. Sounds like the tube is charging. Åtgärd : It sounds like you have a low-voltage power supply problem. Look up the data sheets on some of the larger IC's and verify that the 5-20VDC is present. ----------------------------------------------------------------------------Funai F13TRD1 TV/VCR. Fel : When powered on I can hear the hv charging the tube. There is no picture and the VCR has no function. Åtgärd : It sounds like you have a low-voltage power supply problem. Look up the data sheets on some of the larger IC's and verify that the 5-20VDC is present. ----------------------------------------------------------------------------Toshiba 5135DE TV Fel : starts up with no sound, sound available after 10 minutes warm up. Åtgärd : Check for a coupling cap with high ESR near the amp. ----------------------------------------------------------------------------Samsung TXG2746 TV. Fel : Blew HOT 2SD1887. Replaced with 2SD1885. Pix returns with reduced width and severe pincushion. HOT does not run hot nor does FBT. Åtgärd : The schematic for that set lists HOT Q401 as a 2SD1880. For pincushion problem check CB19 47nf 400v,RE04 6.8ohm 2W,and RE05 also 6.8ohm 2W. ----------------------------------------------------------------------------RCA ctc 169 TV. Fel : Chopper q4101 and regulator u4101 were shorted due to power surge. Now in standby mode, reg b+ is running 176 volts and the set has horiz. frequency squeal and ringing is present throughout the horiz. and regulator section. I tried q4109,q4106,q4105. The pulse at pin 2 on u4101 is spikes instead of squarewaves. The flyback pulse at base of q4106 is ok but the emitter and collector are wrong. In run mode, the set appears to be ok but the chopper transistor runs very hot. Åtgärd : There are three electrolytic caps in close prox of the regulator ic. Change all three items. Also the ic may have sustained damage. C-4102 2.2uf @ 100v, C-4108 47uf @ 100v, C-4104 15uf @ 100v Respective P/N 195691, 193623, 189982. Reg ic is P/N 200419. The problem was caused by a leaky zener diode cr4122 rca#200158. Also replaced at the same time was electrolytic c4108 47uf@50v. ----------------------------------------------------------------------------RCA TV Fel :Where can I get a S2000N transistor? It is a HOT for an RCA TV. Åtgärd : Try an ECG2354; d1887, or d1885 may work for you. Suggest getting original if you can but these should get unit functionsl if there is no other problem. BTW ECG had a nice cross reference downloadable @ ecgproducts.com, check it out. ----------------------------------------------------------------------------Phillips 19" TV chassie # 19s114-00aa. Fel :I need the part # for Ic 351 and a source. Åtgärd : If the microprocessor is Toshiba made, the part# is 4835-209-17315. If it is Signetics made, the part# is 4835-209-47106. These parts can sourced through; Raybel Electronics 9712 Notre Dame Street, MONTREAL, Quebec CANADA H1L 3R2 Ph (514)352-9071 Toll Free 1-800-361-5970 Fax (514) 493-3481 Fax toll free 1-800-363-3481 Email [email protected]. ----------------------------------------------------------------------------Sony kv32xbr26 TV, Fel :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? Åtgärd : 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 ----------------------------------------------------------------------------1: Pair of Philips 27b800 chassis Fel :that the eeproms were bad in. Replaced with factory number, got into service mode and every thing will adjust correctly, vertical height, etc. Once the registers are set, we can exit the service menu exactly the way the manual says, and then unplug the tv to save the registers. We go back in and it is exactly the same as it was when we got started - 06-25-96 menu-->#8- ->set parameters-->go to page "I" or #9 to exit, press volume up to save. At this point the screen says SAVED and shuts off, but when it comes back on, the registers HAVE NOT been saved. Åtgärd : Bad MPU or initilize ckt?? The amin mpu issues the write command folowing the inkey of the correct command sequence. ----------------------------------------------------------------------------Sanyo DS31650 TV, chassis 31650-00 Fel :has no sound after a close brush with lightning. The tube had been magnetized but cured itself. The set will have sound for an instant if unplugged with it still turned on. What components in the audio ckt I have checked appear to be OK. Åtgärd : Something is telling the MPU or Audio to mute, either a damaged active component in the mute ckt or even the MPU or Memory ics themselves. Blitz does create very unique symptoms. ----------------------------------------------------------------------------RCA TV chassis 187AB with tuner on board . Fel : Will not work on channels 2 to 50 (bands 1 and 2). Ok channels 51 and up (band 3). Checked tuner shielding both sides of board. Åtgärd : Call RCA Tech line, there are a few of these that specific coils within the tuner have high resistance connections. The coating on the coil leads needs to be physically scraped clean and resoldered to the pwb. Hav'nt seen a GoldenRod yet but I'm sure that may be next. ----------------------------------------------------------------------------Sony KV-20XBR TV Fel :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. Åtgärd : 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. ----------------------------------------------------------------------------Sony KV-2765R TV. Fel : 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 2-3 minutes when I first turn it on, then fails and comes back after 30 minutes. Åtgärd : Tuner replacement may suffice. ----------------------------------------------------------------------------Panasonic 31 " TV. Fel :When power is pressed, all you hear is a wine sound (which I isolated) and discovered that the power transformer was the source. I replaced it, but the problem still remains. No fuses are blown, and other than that sound, the TV depicts no signs of life at all. Åtgärd : Whine from the power supply is indicative of some type of overload in the supplied circuits. Check each of the loads for excessive draw. ----------------------------------------------------------------------------Mitsubishi cs-28exic TV, Fel :started to go white, but now it just shows black screen with blue dashes running throug it. I suspect the video or pip module. There is sound though. Åtgärd : Try C-7001 on the PIP module. First press menu on the remote and see if the menu is diaplayed clearly. If is is then the pip problem may be your problem. The electrolytic eats away the leads on the pwb. You may need to jump the break or run the cap lead to the pad on the other side of the break. ----------------------------------------------------------------------------- RCA FKC223A TV,Chassis CTC13M. Fel :The picture goes out and there is white raster. It is very intemittent, it plays for days and then it appears, sometimes it stays for a while other times less then five minutes. Åtgärd : CTC131 maybe? Check the connections on the chopper transistor. Also check for poor connections within the tuner and controller assemblies. Check solder connections on video interface board mounted on left upper corner of cabinet (viewed from back). The three video inputs and tuner video pass through that circuit board. Also resolder connections on MCS tuner control module on pins for plug and wires to tuner module. ----------------------------------------------------------------------------Samsung CT-3312V TV. Fel : There are white horizontal fine lines (retrace lines) about 2-3 inches wide on the upper portion of the screen and there is also a foldover on the top. I checked all the elect. caps as well as diodes on the vertical sides and all are ok. The vertical diver also outputs the correct voltage 24V. Åtgärd : Replace the vertical output ic. If that does not fix the problem it is probable that one of the electrolytic condensers in the circuit are at fault. Seen many of these outputs fail without other causes. ----------------------------------------------------------------------------Mitsubishi cs-1983r TV Fel :lost audio only. Changed af power amp (ic 301) with no change. Found the 27v vcc to be missing. Cannot locate where the 27v comes from. Åtgärd : Problem from the scan derived supplies via a fused resistor and diode. Sorry I can't readily identify the parts and locations. ----------------------------------------------------------------------------Zenith System 3 Model #SL2771BG TV. Fel :The low channels 2 and 3 are out and 4 through 6 come and go. Åtgärd : You may order the tuner or the complete board from Zenith parts. I'd go with the board ----------------------------------------------------------------------------Philips 26c614 TV Or Nap PRA927 AKO1 Fel :I need the value of R447, in Philips 26c614 TV. Or Nap PRA927 AKO1. Åtgärd : R447 is 3.3ohm 1/2watt. ----------------------------------------------------------------------------Toshiba cx29711 27" TV chassis tac9165, Fel : works for 30 seconds or so then shuts off. If the power button is pressed, it might come back on. Åtgärd : Have run across this type problem on numerous brands. Here is the general procedure to try on any set displaying this problem. Use isolated variac to reduce ac input to about 90vac. Monitor the ac current draw. Turn on set. It will generally run at this point. Measure output of VR IC. It should increase steadily as the ac input voltage is increased until the VR IC threshold is reached, then the voltage should stablize. Look in a ECG manual to determine the VR IC voltage if you dont have the schematic. I suspect you will find the following if the voltage does not regulate. Look for cracked solder around the VR IC pins (it is always a good idea to resolder them anyway; high failure area). Check around all the connections in that area, the pass resistors, bias resistors etc. for bad solder. I have found that this will cure 85% of this type of problem. Also ESR any electrolytic capacitors in the VR circuit, even if you find bad solder conn. The heat dries the caps out, and they have a high failure rate. (another 5% of the failures). Replace them with hi temp 105 C electrolytic caps and if possible go up to the next voltage range , if there is room. If this doesnt cure it,be sure to check the solder on the pins of the IHVT, and any resistors in that area (another 5%). Another failure prone area to always check, as well as the horiz driver Xformer connections. Is if there is an electrolytic in the primary of the horiz driver tx,always replace it. It will save you replacing the horis output Xistor. This is a high failure cap. especially in the Emerson & other sets that use it. This is a mandatory replacement item in our shop when ever we service a set that uses it, no matter what the set is in for. Most of them will have a higher than normal ESR after just a few years of service. Again use a HT cap and increase the voltage range if possible. This will cure most of the cases. Be sure to recheck the voltage regulation of the b+ line after the repair. It should hold steady up to 140 vac input or beyond. This is the standard test for regulation in our shop. If you still have problems, then try the horiz shutdown area and the xray prot areas. These test procedures were developed over 30 yrs of servicing. ----------------------------------------------------------------------------Phillips TV Chassis model# 19s114-00aa. Fel :When plugged in, it comes on by itself and the sound is wide open. I cannot change the channels but the menu will come up. Åtgärd : This appears to be the same EEprom or microprosser type problem as I answered in P823-4. See that question for a more detailed answer. This is apparently a common PCE products problem. ----------------------------------------------------------------------------Mitsubishi CT 1447LM 14'' color TV. Fel : Main fuse blown, found main transistor\ic in the power supply was short. This was replaced (STR 44115) , now the standby light is coming on, but when remote power button is pressed nothing happens. Åtgärd : The Mitsubishi are notorious for this. If it is an m3 TV, there are two lots of brown stickdown material. One is by the lopty the other is by the secondary of main power supply. Scrape this off as it becomes conductive with age causing the power supply to blow. Also check the zener next to primary fet as it shorts. ---------------------------------------------------------------------------Phillips 19" TV chassis # 19s114-00AA. Fel :When plugged in, it comes on by itself with the sound wide open and cannot be turned off. It will not tune any channels but it does have some OSD. Åtgärd : I have run across a similar problem (except mine was locked into demo mode)on a B8 chassis. To start with, remove eeprom. This should enable you to normally tune set on & off , change vol, and change channels normally. According to Phillips, if the set now works, or works w/ remote , replace the defective eeprom. If not, replace the microprocessor ic. I suspect that you have the same defective part. For me, replacing the eeprom did the job. ----------------------------------------------------------------------------Toshiba cx28400 TV Fel :first had only horizontal line. I replaced IC AN 5521 and R 327 5.6 Ohm. I check with multimeter C 308 is still good, not shorted so I do not replace C 308. Now the picture is cut off on the top of the screen. I adjust the trimpot R 352 for height adjustnent. The height can be adjusted, but the picture still cut off about 1 inch. Åtgärd : Try changing c301 ,c305, 1mfd caps. ----------------------------------------------------------------------------RCA X13101GS TV. Fel :What is wrong when your standby bus starts switching from 0 volts to 2 volts after you turn on or turn off the TV? I already tried changing the system controller chip that didn't fix it. The 5-volt supply is fine. When the TV does go on it works fine. I isolated this bus from the rest of the circuit and it keeps on switching. All of the scan inputs start switching as well. It sometimes will stop switching and go on. Åtgärd : The one I had fixed was not coming on at all. Turns out it was a small npn transistor (switching type) located in the corner of the PCB. The PCB was slightly browned by it overheating & finally it gave out. New one fixed the problem. You can probably use a 2n3904 too. ----------------------------------------------------------------------------NAP TV 19c3 chassis. Fel : Need value for R511, cannot read value. Åtgärd : 15 ohm 1/2 watt. ----------------------------------------------------------------------------Magnavox PR1910C123 TV Chassis 19G6. Fel :Problem No audio, horizontal line across screen (no vertical sweep) with a short raster and Q403 output voltage low. Åtgärd : Replaced shorted D416 and leaky Z406. Set returned to normal. ----------------------------------------------------------------------------RCA ctc169GB2 TV Fel :blinks on and off and then goes off completely. After a while it will play a little while then do the same thing again. Changed the regulator (16 pin) and Q4401 chopper transistor. Checked the horizontal transistor, flyback, several caps, dozens of diodes which all checked good,a pile of resistors. There is 140 volts my 5 volt standby and also 13.6 volts and no other voltages. Åtgärd : We had an RCA with a similar symptom. Try replacing the HOT, even though it may test good. With our set, if we hit the HOT with freeze spray when the set was acting up it would straighten out momentarily. HOT was developing a short when it heated up. Also, watch the current draw on your variac. You will probably see the set start drawing more current just before it shuts off and starts blinking. -----------------------------------------------------------------------------