[ct92404]

I replaced C18 today, and I decided to connect it between pin 3 and the chassis, the way it was connected originally on the actual tv. I'm using a .01 microfarad capacitor, rated at 1.6kv, so it should be fine with the plate voltage.

There might be a very slight improvement with the picture...it seems like it holds steady for a little bit longer. But there is still definitely interference coming from somewhere.

Argus, I don't have another black and white tv to test the signal. It's actually pretty hard to find them now. I could look around in a thrift shop though, and maybe if I got lucky I could find an old portable B&W tv from the 80's or something. Usually whenever I find CRT tv's, they aren't that old, just from the late 90's or early 2000's.

I think at this point, I'm going to have to systematically check the voltage in every part of the circuit and see if it matches up with what's shown in the diagram. As I check each line, I'll mark it on the diagram with a green highlight marker if it measures good. I don't have any fancy equipment, all I have is a multimeter. (Well, I do have a vintage Heathkit capacitor checker but who knows how reliable THAT thing is!) So pretty much all I can do is just basic voltage and resistance measurements. Still, if the voltage isn't right somewhere, that might give a clue about where the problem could be.

I don't really know how TVs work, so I can't approach it in a diagnostic way. I understand that the CRT forms an image by "painting" it line by line with the electron gun and that the electron beam is controlled by deflection coils at the back of the tube. But that's pretty much ALL I know! I'm definitely going to have to do some reading! I'm planning to get that book you mentioned. I actually saw it on Amazon.

- Chris