Hi guys, first post here. I'm restoring a 1978 PET I bought recently and on powering it up today for the first time, was presented with a single bright horizontal line. So no vertical sync. My thoughts are that this could be a CRT problem, but the fact that it's collapsed completely leans me more toward it being an issue on the PCB. I'm waiting for a scope to arrive so I can check.
Pic here - https://imgur.com/a/7qmTGdY
Anyhow, I looked with my meter and am seeing about 4.3VDC on pin 1 of the video connector, about the same on pin 3, and about 1.68VDC on pin 5 (all relative to pin 7).
The cassette drive capstan is also running continuously - my memory of the machine (I had one in the 70s) was that it spins for a few seconds on boot and then stops.
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