In Reply to: RE: These 300B came in today and they Tube DIY asembled but didn't work posted by Thorsten on April 13, 2014 at 11:26:51:
Ciao
I realized that after I had typed it because what I was looking at it on the schematic and there were the words SCR all over the place which I realized meant the capacitor brand..I changed Q2 which I had a close match in stock because it wasn't turning on to give me my negative bias voltage so after fixing the slight crack in the board,the 300b was dropping half of its source voltage across the tube so that's when I changed Q2.
I thought using SCRs were unusual because they are very noisy. I was amazed when I scoped the B+ rails at how low the ripple content was.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
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Follow Ups
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 13:35:55 04/13/14 (5)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Thorsten 13:42:56 04/13/14 (4)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 13:52:15 04/13/14 (3)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Thorsten 14:02:05 04/13/14 (2)
- I figured out why the loud buzz on the one amp when pulling off the grid cap. - Michael Samra 00:34:05 04/14/14 (0)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 14:50:32 04/13/14 (0)