21-CT-55 power supply failure

[Penthode]

Originally Posted by miniman82

The line moves opposite of the picture. That means it's not a drive thing?

Yes, that means that either the retrace is a bit slow or the CRT is not blanked off during retrace. It isn't a drive line that you see.

The one white line is probably a video overshoot meaning that the perhaps a sync pulse edge is causing the line on retrace. The multiple lines to the left of it are the individual cycles of burst. The overshoot will generally be due to IF alignment or if the fine tuning moves the video carrier too far down the Nyquist slope. Do you see the line with the video injected at baseband?

I have seen the line made more obvious if the CRT RGB screen adjustments are set too high: they have to be set to ensure the beam current extinguishes on retrace.

No blooming, seems to have plenty of brightness. BTW, Wayne is probably right about the picture. It seems to be noise, not hum or anything else.

Then that sounds okay to me. If it is picked up at the receiver front end, could it be your workshop fluorescent light?