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Ah ha!
I pulled the focus coil wires off the set and grabbed my trusty Heathkit HV supply...
1) With the wires one way (red + blue -), the coil worked as advertised, and focused a nice bright raster. Well, almost bright enough - it doesn't bloom but there's scan lines at full brightness....
2) Reverse the wires, uh oh - no go.
This makes sense - it's a coil+magnet type focus. If it's 'bucking' the magnet, it's gonna need a lot more ommph to focus. The ommph I measured in the right direction was about 75-100v, into the coil's 1400 ohm resistance. The wrong way, it needs wll over 100v to get even close, and it works like crap anyway.
Checked the schematic. Whoops.
Hooked the wires up the right way - hey neat, you can actually watch this thing now!
With the focus coil's wires flipped and some minor adjusting, I had the best pictures I've had yet on this set. Not amazing, but respectable - almost watchable. There's some gremlins to chase down still, though:
1) Retrace lines - I get these no matter what. Looks like someone's not being a team player in the CRT area.
2) The flyback gets warm. Not hot, but warm.
3) I'm starting to really think that size coil's bad - it was disconnected when I got the set, which had it's OEM yoke (blown). Looked like it was that way a long time, too.
4) Sound has vert buzz. Minor touchup, I think.
5) Larry The Cable Guy isn't very funny at 1:30am.
Question - given that this is a 'bent gun' CRT, does the rotation of the tube vs the focus coil affect anything? I installed the CRT more or less random, but am wondering if turning it a bit would allow me to tighten up the focus, which is pretty good but not what I expected - I can't get a perfect dot, more like a tiny blob.
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