baronbeehive
Headphoneus Supremus
Right, I strongly suspect a faulty connection, most likely on one of the 6 caps you put in, coupling, cathode, or cathode bypasses. The fact that you wiggle the pot only moves the whole PCB, I think if you wiggle any of the tubes the same thing might happen. You might be able to find the culprit by wiggling the tubes and the one causing the worst drop off might be where the fault is.
You will have to take off the chassis top and bottom again, half an hour or so after you've switched off to reduce any chances of danger from the undischarged caps. Never touch anything inside while it is switched on. Look at every connection you made and see if it looks loose, or coming away from the board. You might have soldered over a lifted pad, which is the round connection onto the board, so it would be difficult to see any fault. Sometimes a cold solder will cause this problem, and they are difficult to see. The solder joints should look shiny, not dull or rough looking. If you gently pull at each connection you might see any loose movement. If it is a lifted pad then you will have to make a proper repair…. I had to do this. Lifted pads can happen when you pull out old components, or if you put too much heat or pressure on the joint when soldering.
The best way to find a faulty joint is by using a multimeter and testing for continuity, but since there are so few new joints made with these mods you should be able to detect anything faulty easily. Anything suspect should be resoldered. Make sure no wires are touching or loose.
Also check the wires are not broken when you put back the chassis top plate. Also make sure there's no blobs of solder lying around, they can cause shorts.
Can you take any pics of the joints.
Really any soldering should be checked with a multimeter for continuity with all connected components which would show up any problems, because if you don't do this you won't know if there's a problem, and you could short out the board and components.
If in doubt this would be an easy job for an electronics engineer to fix.
You will have to take off the chassis top and bottom again, half an hour or so after you've switched off to reduce any chances of danger from the undischarged caps. Never touch anything inside while it is switched on. Look at every connection you made and see if it looks loose, or coming away from the board. You might have soldered over a lifted pad, which is the round connection onto the board, so it would be difficult to see any fault. Sometimes a cold solder will cause this problem, and they are difficult to see. The solder joints should look shiny, not dull or rough looking. If you gently pull at each connection you might see any loose movement. If it is a lifted pad then you will have to make a proper repair…. I had to do this. Lifted pads can happen when you pull out old components, or if you put too much heat or pressure on the joint when soldering.
The best way to find a faulty joint is by using a multimeter and testing for continuity, but since there are so few new joints made with these mods you should be able to detect anything faulty easily. Anything suspect should be resoldered. Make sure no wires are touching or loose.
Also check the wires are not broken when you put back the chassis top plate. Also make sure there's no blobs of solder lying around, they can cause shorts.
Can you take any pics of the joints.
Really any soldering should be checked with a multimeter for continuity with all connected components which would show up any problems, because if you don't do this you won't know if there's a problem, and you could short out the board and components.
If in doubt this would be an easy job for an electronics engineer to fix.
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