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Old 11-26-2012, 10:17 PM
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Quote:
Originally Posted by cdmarion View Post
Ive also noticed that when i turn the bright control all the way up I lose my audio signal . . . . . I don't lose audio gradually, just in the last bit of turn of the control the audio will just shut off.
Is the pot shorted or open? A short could be pulling down a B+ line. The Crosley's with the cat-eye tunning usually fed the brightness pot from both ends.

I would expect that the contrast control (actually an IF gain in some Crosleys) could muck up the audio, but not the brightness.

Quote:
Originally Posted by cdmarion View Post
I've checked the voltages at the 12au7 video amp and have pretty much 0 at tpin 6, plate, I should have 185vdc.
OK, that is a very good clue. Use your Sam's tube pin resistance measurements and/or just trace the circuit back the B+ (or possibly B-boost) and find out where it is being lost. (Actually pull the tube first and and repower the set to see it this restores the plate voltage. This could be a simple as a shorted tube.)

If you or someone has a schematic of the video, vertical and CRT sections and could post it, it would help.

James
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