What could cause this?

[old_tv_nut]

Originally Posted by SpaceAge

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I have started to notice the picture size will fluctuate slightly with brightness changes. It's most obvious with news banners along the bottom of the screen. I don't think this is a new issue, just something I've recently noticed since I've been running it a lot lately to keep an eye on corona coverage. The picture is watchable but I'm curious if you experts have any ideas about this before I tear it apart again...

CRT TV size regulation is seldom perfect. Without seeing it in person, I'd guess "fluctuate slightly" is normal.