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Old 07-22-2021, 09:33 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is offline
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Join Date: Nov 2018
Location: Round Rock TX
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Quote:
Originally Posted by Electronic M View Post
I started messing with the chassis last night. Got full vertical by resoldering a cracked joint on a 500uF 10V vertical lytic that some tech had snipped a lead then badly tacked it back together.

I couldn't get it to pass VHF 13 from my agile modulator, but did get audio either from it or FM. I was able to get it to pass IF from my B&K analyst and discover monochrome video passes, I have sync on both axes, and color demodulation seems like it's atleast somewhat working.

The high B+ rails are only 30V low one of the lower ones is a bit worse though.

The 16KV HV (focus is about half what it should be too) is a bit confusing. H Out screen was about 10V low and control grid was at -28V instead of the Sam's -50. There's a terminal that a note on the chassis says to ground if the H drive is insufficient doing that got me -44V at the grid and the screen 10-20V higher than Sam's. This didn't change HV. Unplugging the CRT and HV reg aren't increasing the HV and neither is disconnecting the ground of the HV doorknob. Strangely the boost is only 30V low.
I need to go through the recap the previous owner did with a fine tooth comb now though. There's mistakes. Sam's shows 2 different .22uF 1KV caps connecting flyback lugs to centering pot terminals...one was replaced with a pair of parallel .1 400V caps (that they aren't shorted is a miracle) and the other one looks like a .1 at 1.5KV out of a late 60s Philco.
I'm hoping the HV issue is just some wiring or part error but if it isn't finding it is going to be fun.
That poor solder joint makes me cringe, also the lack of tubing on the long leads. :O
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