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Old 09-10-2015, 06:55 PM
Doug66 Doug66 is offline
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Join Date: Sep 2014
Posts: 166
Hoffman 610 Lost B+

I think I'm in over my head on this one. I got this from a fellow member, and it was unrestored. I was told it would get a partial raster, and that's all. I was hoping a simple recap would do the job.

I started recapping the electrolytics and paper caps, and I got the raster almost full, but no signal yet. When I ordered the last electrolytics, I also decided to replace the 2 candohms R178 (1650) and R 174A (1500).

When I tried a power up after this, I had no raster and no B+. I have checked and rechecked all my work and even disconnected everything from the filter choke, then connected it up one by one.

Here are my findings: When I disconnect R206 (560ohm) from pin 4 of V105, the B+ goes to about 30V. With it connected, I have about 8. Disconnecting either side of R178 givers me the 260V I need. I even hooked up the old candohm of R178 to make sure I had the right part in. Putting the old one back in didn't help.

Any Ideas on where to go now?
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