Nobelium - tube bass preamp project

Hmmmmm.......I have never seen a 12AX7 tube used for V1 neither, and I think the XLR PCB is back to front as well from what I can see.
If I had seen this on April 1st I would have thought it was a joke, come to think of it it is a joke since absolutely nothing is correct
 
Wondering if anyone can help me. This is my first project. both xlr and 1/4” out and tone controls work, tubes heat, everything is good except for the LED on the left board. When I measure voltage on the positive leg of both LEDs I get the same value, I can’t for the life of me figure out why led on the right lights and the left doesn’t.

Any suggestions on how to troubleshoot this?
 

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Schmavirz said:
Wondering if anyone can help me. This is my first project. both xlr and 1/4” out and tone controls work, tubes heat, everything is good except for the LED on the left board. When I measure voltage on the positive leg of both LEDs I get the same value, I can’t for the life of me figure out why led on the right lights and the left doesn’t.

Any suggestions on how to troubleshoot this?
Click to expand...
I would first double check that the LED polarity is correct, and that the LED itself is actually good. If the LED is oriented correctly, try reflowing the pins from the tube board to the main board and confirm continuity between the boards.


If you're seeing voltage on the LED positive leg but it isn't lighting, it usually means either the LED is bad, installed backwards, or the ground leg doesn't have a good connection.
 
chongmagic said:
I would first double check that the LED polarity is correct, and that the LED itself is actually good. If the LED is oriented correctly, try reflowing the pins from the tube board to the main board and confirm continuity between the boards.


If you're seeing voltage on the LED positive leg but it isn't lighting, it usually means either the LED is bad, installed backwards, or the ground leg doesn't have a good connection.
Click to expand...
The ground legs both show the same reading too, (different from the +, but the same LED to LED), and this LED works when inserted into the right board.
 
Nevermind, was measuring wrong, it gets no power. I have reseated everything on the board, but still nothing.

However the Tube heats up and the nobeliun functions as expected. Any advice? Should i try to get a new tube board, socket, snd 2x5 connector and redo everything? Is it insane to swap the left and right tube boards to see if that makes a difference on the left side?
 
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