CTC 169 Proj.

Thanks for taking the time to read this, again, (only if you've seen this before) of course! This 35" RCA is still driving me nuts and I'm taxing my nerves here. The problem this set has is as follows. With any input, (rf, composite), the video is distorted, I mean, the image has an "S" type wave just near the top of the raster, it'll migrate down a little and just above the "S" bend it'll has vertical stretch bars, about two inches worth!?!? It'll lose vertical sync sometimes if channel is changed. The raster is shifted to the left approx. 2" Chroma either disappears or is severely skewed.

UPDATE: I've since tried the S-video input and have the same result. I don't want to give up here, this set is NOT going to win....period!

I feel like I'm chasing my tail.

TIA

Cheers, Steve

Hi Steve...

Just a thought from an old long retired guy, if I may?

What you're describing sounds as simple to me as AC in your video.

Have you checked power supply filters? Perhaps a cracked solder joint at a filter? Might be worth a few minutes of looking at the dc lines with a scope; look for 60 cycles (or perhaps 120) riding on the dc.

A hint that might make this more plausible is it the s curve you describe _very very_ slowly walks through the picture vertically. (I'm pretty sure it does, given that on occasion it interferes with vertical sync)

Take care.

Ken

Thanks Ken, I'll check the supply caps today and post my findings later. Now that you mention it , I remember getting a more dramatic result a year ago or so, from another like this one, turned out to be main filter cap, ( 860 uf 200 v), it had not vented, but man, there was pressure built up inside that sucker. You see, it had puffed at the top. I just barely cut open the can near the top and electrolytic started spraying out, never in 20 years have I seen this!. That set had a chattering stepdown xfmr and much of the same symptoms. Also, that "S" bend does migrate, so.... BTW, OSD is centered and not, I say NOT affected. That makes perfect sense, an AC ripple corrupting info thoughout, I'll especially check low voltage supplies. Thank-you. Cheers, Steve