Ok guys, so today I hooked everything up outside of the cabinet (a little easier for me), and fired it up. First off, in my research I found that 'Instant Play' meant that the tube filaments were always on at a low voltage to give a quick startup... but it looks like they're on 100% filament voltage with the set off, that seems so stupid to me O_o. ANYway. I turned off the lights and watched the tubes for any red-plating, of which I could see none. So I let it run for a bit. Still I think those tubes are getting abnormally hot. I'm aware that tubes are by nature warm, but this set could double as a space heater.
Oh, also, how important is the grounding spring that touches the aquadag on the screen? Could I test-run the set without it? Because it's a pain in the ass to keep the spring in place without the cabinet assembled.
Um, at first power on, I had about 3/4 of the horizontal going. after about 2 minutes, the horizontal was getting weaker noticably, and at about 4 mins, it lost horizontal altogether, leaving just a flat line on the screen, at which point I turned it off.
There's no way this could be caused by a tuner tube, is there? Cuz the VHF RF amp (3HA5) tests very weak. Doubt it, anyway.
I let it rest and turned it on again, it started sparking. I resoldered one joint and that took care of it. This time it again started with about 3/4 of the vertical and slowly lost it. Now I didn't see any
red plating, but I did see some blue... plasma arcing whatever, inside the AGC video amp & sound IF amp (14BR11). I'm assuming that means it's gassy? I wasn't able to capture it on camera, but I'm pretty sure I wasn't hallucinating.
Quote:
Originally Posted by old_coot88
Be really careful turning that slug with an allen wrench as it's very fragile powdered iron and cracks easily. There are special tools called alignment tools ('diddle sticks') made for that.
The 33GY7 obviously has grid drive since you have a raster. Taking voltage measurements on the tube wouldn't really gain you anything.
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No worries mate. It moves very freely and I was gentle with it. Also messing with it made no improvement. :/
Quote:
Originally Posted by tom.j.fla
The numbers & letters stamped on top of the flyback box will be your chassis number.
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Thanks bro! T7H2-1A, so I'd assume H2-1A?
Quote:
Originally Posted by zeno
IIRC the old Sams index on disc will do MUCH
better searches. Last resort is to find a similar chassis. Any
Admiral with the same tubes will be almost identical. I can help
with that.
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Help? Please? :3 It says T7H2-1A on the flyback box. There are also lots of numbers on the PCB. I do have the
serial number, but I doubt that'll help.