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Old 03-21-2021, 01:21 AM
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Yamamaya42 Yamamaya42 is offline
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Join Date: Nov 2018
Location: Round Rock TX
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And so it has begun, a quick test with the 8yp4 test CRT showed me I had good HV and horz sweep and NO vert, I thought OK, most likely due to bad caps, but I did see that some work in the area had been done before. After a bit of poking around, found OK voltage on the plate of the Ver output, but in the plate of the Osc, nothing... 0 volts.

Which was tracked down to a bad Osc transformer
one winding is 1k,, the other SHOULD be 200 ohms, wide open... already found a new one.

what I'm facing getting a replacement CRT

what was in there
https://frank.pocnet.net/sheets/093/2/21EP4A.pdf

As mentioned, this is a magnetic focus 70 degree tube
one option
https://frank.pocnet.net/sheets/093/2/21XP4A.pdf
another 70 degree tube but electrostatic focus and slightly smaller dimensions

the other option
https://frank.pocnet.net/sheets/093/2/21AWP4.pdf
this is a magnetic focus 72 degree tube which seems to have exact electronic footprint of the original tube but has slightly larger dimensions ( can also be made to fit )
Choices choices :O
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