A note on a "Tough Dog" Vert problem

I do not remember the exact cause, too many years back, but likely it was.

1. Was the problem heater-cathode leakage in that Zenith B&W CRT? I had a similar Zenith set back in the mid 1970s that I fixed up to use in my bedroom.

2. I got to thinking after reading your post that if we had this forum back in the mid to late 1980s I might have consulted you about color burst circuitry to help out an undergraduate student with her class project. I was a graduate student back then at Memphis State University. I just had a vague understanding of how the color burst circuit works and couldn't be much help. Back then the VCR was king and she wanted to be able to use the color burst signal (or lack there of) to prevent commercials from being recorded off air. Something about the fact that commercials back then didn't have consistent, stable color signals like regular programming. That's what I remember anyway. 

73, Roderick  WB6FBF

The first TV repair shop I worked in had a set that vexed the store owner, the outside tech, and the bench tech. (Myself- I was a roustabout at that time).

 They all fought that set for close to 2 weeks.
 Finally the bench tech found the problem- leakage in the CRT .

I have never seen that problem since either. It was a Zenith 17" B&W set.

 He had a brainstorm and hooked up the CRT from another set to the chassis and the vertical problem went away. A replacement CRT sent the set home to the owner.

 That was 50+ years ago. It was so odd a problem, I never forgot it.