Thread: 65 maggie
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Old 02-05-2015, 11:58 AM
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DavGoodlin DavGoodlin is offline
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Timmy,
Check your email at 1:20 pm. I scanned a Magnavox "series 45" schematic (CTC16 variant) which you have. The only thing is, there are no voltages on the tubes, only sources like 405 volt supply, etc.
I am ALSO sending a series 41 (similar to CTC12) schematic which HAS VOLTAGES on all the tubes.
On a 41, the blanker feeds into demod tubes' cathodes and the CRT bias sets the bias on the CRT via the B&G drive controls.
Also the 41 schematic shows you CRT voltages:
cathodes =322 volts
G1s = 195 volts
G2s = 700-735 volts

The 12GN7 should measure about 250+ volts on plate pin 7 if too low, pix is bright, too high and pix is dark.
Dont forget that 100 mf @ 25 v cap across the contrast control, jump in a new one

Whatcha got for volts on CRT pins?
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