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Update!
Well, I soft-started it yesterday afternoon, and when I ran it at normal voltage, and turned up the brightness far enough, I was greeted with a almost invisible and poorly focused raster with a brighter (but still dim) narrow shimmering vertical rainbow of color that appeared on the right-hand side of the CRT. The 'rainbow' only appeared when the brightness and contrast controls are advanced at least to their halfway points. The vertical and horizontal hold controls behave normally. The hue and color controls have no effect on the raster. There is no audio except for random static (which indicates at least the AF output stage is okay). Rotating the channel selector does produce some visual and audiable 'noise' as the switch contacts change, but that's it.
Well, at least it has a raster..! I let it run for a few minutes, and nothing seemed to get overly hot either, so that was a good sign. The flyback was still cool after I shut off the set. One thing that surprised me was how *quiet* the HV section was. Normally, I can hear the horizontal oscillator of TV sets (especially old ones) fairly well, but I didn't hear this one at all. Before I first swiched on the set, I set the brightness control almost all the way to its minimum, so I was really surprised to see anything on the screen when I turned up the brightness, since the lack of horiz oscillator whine made me figure the HV wasn't working.
One thing I quickly noticed was that the heater of the 1V2 focus rectifier wasn't lit. while the set was on, I pushed at it with a wooden stick just to see if it was a dirty connection, but that didn't do anything. The 1V2 gets its heater voltage from the flyback, but the 3A3 HV rect also does (though via a separate winding), and its heater was lit.
I saw only about 200V on the 300V B+ line (measuring it on the wiring harness that goes to the tuner), so I'm sure there's something fishy somewhere causing that. As I was still wondering about the dark 1V2, though, just for fun I replaced it with a new one (since I happened to have a few of those around) to make sure it wasn't something flaky in the old one (though it tested okay in a tube tester, and has a quite visible heater). The heater didn't light up with that one either, though the raster was now noticibly brighter for some reason, and now it produces a rather trippy pattern of colors whose colors change with the setting of the brightness and contrast controls. The focus is too poor to be able to dicern the individual scan lines, but if you turn the contrast control up enough, you can see what appear to be blurry retrace lines. The raster fills almost the entire screen even at low brightness, but blooms (and defocusses even further) if the brightness and contrast controls are advanced far enough. Note: I have not degaussed the tube or anything like that yet, so I'm sure the purity is going to be bad no matter what.
Questions: with B+ as low as it is, is it normal to even be able to get enough HV to see a visible raster on the screen, yet not have enough B+ for the IF stages to work? (I haven't measured the 380V B+ line yet, but I would suppose it is proportionately low) Of course, these could be two totally separate problems. Also, why would there be enough HV to get the HV rect tube to light up from its flyback winding, but not the focus rect? Hope it's not the flyback itself that's bad... One thing I noticed is that someone had jumpered a resistor connecting the focus rect to the CRT, so perhaps that's a clue about something. In any case, I would suppose my next step is to find out what the deal is that's causing the low B+.
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