driver testing [resolved]

joralieu · 1264

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Offline Paul Birkeland

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Reply #30 on: May 09, 2024, 04:17:44 PM
There's a terminal labeled "X" on the PC board, can you measure the DC voltage on that pad on the side where you have 15V at Kreg?  Also it wouldn't hurt to just swap the 5670 tubes to be extra sure this isn't something that's tube related, though that seems quite unlikely under these circumstances.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline joralieu

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Reply #31 on: May 09, 2024, 04:31:35 PM
I get 2.9V at X I have swapped the tubes and it made no difference



Offline Paul Birkeland

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Reply #32 on: May 10, 2024, 04:55:23 AM
Fundamentally this may have a lot to do with the 2.49K and 249K resistor swap.  You could try replacing the 431 regulator there, and that might work, but you may also just have an iffy joint or a lifted trace on one end of the 2.49K resistor on that side of the board.  I would probably pop in a new regulator and add a little heat and solder to the 2.49K resistor.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline joralieu

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Reply #33 on: May 10, 2024, 12:45:33 PM
I reheated the 2.49k resistor and everything measures right now. Sheesh I knew it was something simple.
Thanks
Joe