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First of all, please excuse this super simple question. I know nearly nothing about electronics, and just want to make sure my understanding of this is correct.


So I ordered two of the same audio amplifier board (from different sellers), and the first one's potentiometer just sort of fell apart as soon as I inserted a screwdriver. I tried but couldn't but it back together.

the two boards, with broken parts on top

I think, I don't need to mess with the amplifier's volume for this project, and I was planning on having it turned all the way anyway.

The exact model of the pot on both of them, I believe, is RM065-103 (datasheet here).

I have no idea how to read schematics, but I'm guessing that to replace it, (after desoldering and removing the pot,) the 1 and 3 pins (in/out?) should just be connected directly, and the 2 pin (gnd?) just be left alone, like this:

bottom of boards with proposed wiring

Is this the right approach to take? I tried researching a little bit and I think I might need to have a resistor between the connection, but I'm not sure.

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I expect that the terminal you marked "2" is the wiper (moving contact), and "3" is the top (ungrounded, input) terminal. If you want maximum gain with the pot removed, jumper "2" to "3".

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  • \$\begingroup\$ +1 and you don't need to remove the pot- the element can remain in place. \$\endgroup\$ Nov 20 '17 at 4:00
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You are basically correct, but not quite. It's true that you need to desolder the pot pins then replace the pot. However, I'll pretty much guarantee that all 3 pins are connected to the circuit, so you can't just "leave the pin alone".

And in this case, desoldering is made easier by the state of the pot. Take a pair of sharp cutter, and cut pins 1 and 3 at the body. Then melt the solder on pin 2 and pull the lead and body away from the board. Then unsolder 1 and 3 while pulling with a pair of needle-nose pliers to remove them. Now take either some desoldering wick or a Solda-Pullit and clean out the holes, and install the new pot.

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