Hope you see a new tip / idea.. GL "joe" =============================== CTC169 chasis, model#f27188bt. The original problem was a dead set condition caused by a shorted cr4101.After replacing the diode the set powered up ok and the video was good except for overscanning in the horizontal.Both sides of the picture are cut off.I tried to adjust the horizontal width pot but it had no effect.Is there a service menu I must access to adjust paramiters in an e-prom like the ctc177 chassis?
ANSWER 1: Excessive width usually caused by shorted PCC Diode (use ECG577) & Yoke return cap...either .047uF/400v or .056uF/400V. (Square,blue or grey plastic case) This cap is next to the PCC diode & MUST be replaced at the same time. ANSWER 2: Sounds as if the pin damper diode and associated capacitor aprobably damaged. Diode is physically located in front of horiz output. Cap is a .056uf or similar in value. Cap may appear slightly swelled. Common failure that can destroy hot transistor. =============================== RCA TV, model F35751MB CTC169BG5 Vertical High and corner words lose (PIN CUSHION PROBLEM). Do you have procedure for imput to eeprom configuration? Change the Pin Damper diode and associated cap [ usually .056 ]. You will find the cap slightly swelled due to internal pressure. Common 169 problem. =============================== Proscan ctc169c15 TV.� After a lapse of time, the horizontal output blow.� Is this possible that it is produced by overscan? Check the regulated B+ at the collector of the horiz output while in standby mode. It should be less than 145 volts. If it is higher you have problems in the regulator circuit, probably a capacitor going bad. The other fairly common thing, that is very apparent, is the failure of the pincushion cap and damper diode. The original cap is blue in color, if it is failing the sides of it will be slightly swelled.� Third possiblilty is the horiz yoke return capacitor, physically in same area as the pincushion cap and diode. Of course, you may have an ivht or crt giving problems. Most possible by an arc in the crt, or more probable, a fault in the B+ regulator circuit. There are a couple of electrolytc caps in the regulator ckt that dry out and allow the regulated B+ to go too high. Usually the shutdown occurs before the h-out device fails. Also check the horiz yoke return cap and pin diode and cap =============================== Admiral TV with G.E. ctc167r chassis, picture collapsed, no vertical, cr4802 burned up.� Replaced with specified substitute, vertical came back but picture now bowed in on sides about 1-1/2".� Replaced horizontal output q4401, no change.� Checked c4406, c4402, c4403 all seem o.k.� Measure 24 volt on q4804 instead of 15.2 specified in schematic. Horizontal width control has no effect.� Next step is to replace all pincushion transistors, but still feel problem linked to the burned up cr4802. After repair of vert, if unit has hourglass pix ) (, My fix was CR4403 part# (164589). Other possibles though, CR4401, C4407, C4403 =============================== RCA chassis CTC169BJ5 which had a shorted Horizontal Output Q4401 which was caused by a shorted Vertical Pincushion Transistor Q4802. After replacing both components, the set will operate for 30 minutes then Q4802 shorts again causing a pincushion problem and, within a few minutes, shorting the HOT again. Replaced all caps and diodes in horizontal deflection/yoke circuit-no help. Shortout of Q4802, pincushion output transistor, is caused by faulty, shorted coil from C of Q4802 to deflection (flyback and damper diodes).� Coil as part of LC filter not supressing spikes from deflection anymore overloading and giving pincusion out transistor too high Ubeo. =============================== CTC169 / G35830WK FIX:-C4403 .48Uf measured .319. replacing it restored normal width. I was all over the horizontal circuit but never considered the yoke return cap. I have seen plenty of these open but never just partically open. I had the same problem awhile back. I don't have print in front of me but it turned out to be a .48? cap in the yoke return circuit was down in value. On this set the picture is too wide. Unlike the common problem of too wide with curved in sides this picture has straight sides, just too wide. C4401, 4402 are good but replace them anyway, CR4401, 4402 are good. Regulated B+ is good. =============================== [EMAIL PROTECTED] From: [EMAIL PROTECTED] (<[EMAIL PROTECTED]>) Date: Sat, Jan 10, 2004, 2:55pm To: [EMAIL PROTECTED] (ELECTRONICS PROFESSIONALS LIST) Subject: Re: [Techs] TA RCA CTC167CS Pincushion**Urgent/ Reply�to: [EMAIL PROTECTED] (ELECTRONICS PROFESSIONALS LIST) Model number was in the thread, but Parts Finder says it is a CTC169 manu 1995. This set is dated 1990 on the rear Model F27194SM I replaced the capacitor and no change except a little more narrow..I grabbed one from another chassis.. I replaced the linearity coil and set was still bowed, with pincushion and a lot more narrow..pulled this from another chassis. The coil I used from another chassis which would explain the narrow pic, but it was still bowed, so I don't think a new one will help. With the different capacitor C4403 the picture is not quite as wide, but since I still see the bowing(hourglass) I assume a new one won't fix that. Any other ideas? Jeff Dougherty Intrepid Video TV/VCR 263 S Front St Steelton PA 17113 fax...717-564-4952 www.intrepid-video.com www.tech-repair.net Joes....Electronics �(Joe:Tech/2004) [EMAIL PROTECTED] Fax::509-479-2283 _________________________________________ Please include original text when replying to this email. Once you get your unit repaired, please post the fix to the group. Order your tech repair CD today, Version 3.0 only $49.00-more monitor tips-user friendly program. [EMAIL PROTECTED] www.tech-repair.net ______ Techs mailing list [EMAIL PROTECTED] http://intrepid-video.com/mailman/listinfo/techs_intrepid-video.com Go to the link above and scroll to the bottom to enter your email address
