1949 DuMont - issues when turned on cold

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Originally Posted by Gleb

It looks like B+ is coming up slowly. The brightness control and the vertical sweep section seem to get power from the same line. Can you measure it while the TV is warming up?

I will give the schematic a look at this circuit to try and see where the brightness control and vertical sweep section get their B+ from and see if I can ID any issues from that common point back.

Thanks for these clues.