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Today I inspected it and found it in good shape underneath. Except the interlock was defeated and the 117 AC connected in the air and not insulated!
I removed both rectifiers and slowly turned it up on a variac. All AC voltages looked ok on a scope (I have scope probes up to 50 kV.) Not all tubes lit or got warm.
Inspection showed tubes in wrong sockets and only one 6N7 ... the socket wirings are both clearly that and not 6SN7. Correcting that (for some reason I can't recall I stock 6n7s!) resulted in all tubes lit or warm. I then inserted the 2V2 and again turned it up very slowly on the variac with dim bulb. The HV got to 2.3 kV with no distress after about 20 minutes, so I removed it and ran the HV up to 3kV, again with no distress.
I then disconnected the HV at the 117 line.
I powered it up very slowly with a 5U4, variac and a 300 watt dim bulb, getting it to 85 vac in a couple of hours. No cap or resistor got hot. I used a scope to verify that the horizontal and vertical oscillators were working. The RF oscillator didn't. I replaced the dim bulb with a kill-a-watt and 3 amp fuse. I slowly raised it to 117v with no distress. At 89 volts the RF oscillator started.
I then investigated both sweep output stages. The horizontal was OK but the vertical was not. It had both phase outputs, but one was a bit low voltage and the other was very very low. The set set could never have worked completely
OK vertically in this state. Inspection showed the problem instantly: the stage is miswired. That is enough for today so I went out for a burnt ends BBQ sandwich.
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