4 replies to this topic

[jamesk]

Note: I've worked with high voltage circuits before.

I have a very nice looking 1989? RCA G26231 TN Analog TV. I just know this thing would rock for classic gaming. The only problem is that it has some bad image warping using the composite RCA jack (see below). I took the TV apart and looked it over. It was very dusty but also had some hot candle wax spilled inside it. I cleaned out what I could, but it looks like I'll have to take out the main board for a good cleaning. All the components are thru hole, so that's a plus.

If someone could give me their guess to what to look for or what part of the main board circuit is the likely culprit, I would be grateful. It might save me some troubleshooting time.

Edit: This is a CTC156/156

Edited by jamesk, Thu Dec 8, 2011 5:55 PM.

[bust3dstr8]

Vertical collapse can usually be fixed by recapping the whole chassis. I would recommend 105° Nichicon or Panasonic, they are
a lot better than the crap in Radio Shack...you can find them for pennies each at Mouser.

[candle]

i would rather replace two capacitors in vertical deflection stage
one is on its power supply (usually 1000-2200uF/35V or more) the other is around 330-470u/63V and its responsible for such effects
this is charge pump capacitor, and if its failing, then vertical stage can't give exact voltage ramp needed for deflection coil

[jamesk]

Thanks for the info. I'm going to recap the whole thing. I figure I might as well if I'm going to have the board out.

[Stephen Moss]

Does that only occure when using the RCA input or does also occure via RF (from the same source)?