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Yeah, that is my thought too. Here's where I am: I cleaned up the burned wiring, checked resistance on all of the B+ lines and found it fairly high, and brought the device up slowly on a variac. At 235VAC, I have all three B+ sources putting out the exact 225, 150, and 75V that they should; powering on and off I can see the filters charge up and back down as expected. That melted 7W 220Ω resistor gets pretty hot, but I think that's to be expected under normal operation.
The bias supply works as expected.
The screen on the CRT doesn't light, and I'm not getting much of any useful signals from the various jacks around the front panel:
I do have 1kHz audio, though the waveform isn't exactly a sinewave - it looks more like, I dunno, nipples from an old-school baby bottle, I guess?
The vertical sweep drive has a very messy sawtooth waveform. Horizontal has nothing. Nothing on Sync, nothing on Color. I haven't tried the others yet.
So I don't know what caused that meltdown, but it seems it's not there now - a screw fell out when I took the bottom off, I wonder if it had maybe shorted that B+ line to ground? Tomorrow I'll start trying to track down what's not working right, I'll check for boost, and see if there's any other test signals available. Since I really don't understand how this whole circuit works I'm kind of feeling my way in the dark.
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