1950s or '60s vintage Zenith TVs, Need some info

[Kevin Kuehn]

It appears your yellow screen grid bypass cap was jammed right up tight against the Horizontal Output plate lead soldered to pin 7. That's the Do Not Measure point on your Sams schematic. Speculating but it's possible high voltage burned through the outer plastic film trying to get to the ground layer. Or the socket terminal could have knifed through the insulation. It also looks charred down inside the center of the socket base. The 8.2k doesn't show any sign of heat, so it likely was not part of the short.

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[vortalexfan]

Originally Posted by Kevin Kuehn

It appears your yellow screen grid bypass cap was jammed right up tight against the Horizontal Output plate lead soldered to pin 7. That's the Do Not Measure point on your Sams schematic. Speculating but it's possible high voltage burned through the outer plastic film trying to get to the ground layer. Or the socket terminal could have knifed through the insulation. It also looks charred down inside the center of the socket base. The 8.2k doesn't show any sign of heat, so it likely was not part of the short.

[/url][url=https://flic.kr/p/2mWKTQ3][/img]

Well that's actually right near where the original cap ran, the only difference was that the original cap was a bumblebee cap that had a non-conductive plastic cover over the paper and foil electrolyte roll.

[Yamamaya42]

But I do see what KK was getting at, that cap should have been as far away as possible from that joint, where as the cap is like rated 630v, or what ever, the voltage at that point is MUCH higher, and could very easily find a way to burn into the outer layer of the newer cap, where it did not of the older style one.

There is also a chance the wire to pin 7 is damaged ( carbonized) needs to be looked at closely.
Not only could this high voltage found a path to ground, but it may also have gone the other way to the bias on the other side of the 5w resistor, and hit your CRT, (not sure of how your set is wired), but via focus or the brightness or video output.
Thus I mentioned having to check stuff.

[vortalexfan]

Ok so I finally got the Bugeye TV going the rest of the way. 👍😁
See picture below for the screenshot I took.