[TinCanAlley]

Originally Posted by andy

It doesn't look that bad to me. I think your scope is showing more of those sharp negative going pulses than what ever scope Sams used. If you ignore that really fine negative pulse, it ends up being around 8-10 volts which is well within reason. I doubt Sams would have used a 100MHz oscilloscope because no technician in the 70's would have had anything even close to it.

I can just about guarantee nothing in the HOT base drive circuit is causing your jail bars. Generally, if there's anything wrong with the base drive, the HOT will overheat and fail. The HOT acts as a switch. It's either completely on, or off.

I think you need to be looking around the flyback, and yoke. Something is causing the flyback, or yoke to resonate at about 10x the horizontal scanning frequency. It's not going to be caused by a slightly wrong drive signal, or slightly off voltage.

Have you looked at L218 and C274?

Okay, just to make sure, is this attached pic of the L218 you're referring to (the brown cylinder with the coil around it)? It took me a moment to find, but it is connected to tie points 3 and 4. I should check its resistance and see if it matches what Sams has across tie points 3 and 4? Also, I can't find the capacitor shown (the .047).

You have any tips on checking the yoke? I've been trying, but I can't see to get any meaningful results. I've tried checking pin pairs, but according to the schematics, each has multiple connection points. So how am I supposed to check the resistance? All I can really do is check continuity. The first pair I tried should have a resistance of 220ohm, but my meter shows me 8ohms.