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I have an old set of computer speakers. The 10k potentiometer broke off, and now I'm trying to figure out how to rig it to 100% volume without the POT.

The POT appears to be dual channel, and has a total of 6 terminals on it, all of which are in use on the PCB.

PCB Top

PCB Bottom

I cannot make any rhyme or reason out of this, when it comes to understanding how this is implemented. I'm looking for a way to not replace the POT, but instead install jumpers or resistors to complete the circuit at 100% volume. I just can't figure out what to connect to what, as it's not clearly labeled what's what.

How should I rig this up to work?

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  • \$\begingroup\$ see this ... build-electronic-circuits.com/potentiometer \$\endgroup\$
    – jsotola
    Commented Apr 7, 2018 at 1:05
  • \$\begingroup\$ @jsotola I'm familiar with how a POT works, I'm just having a tough time figuring out which terminals to use, as they're not identified here. \$\endgroup\$
    – Jerry Dodge
    Commented Apr 7, 2018 at 1:10
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    \$\begingroup\$ Upon closer inspection, I can see now which one is ground. That big solder blob in the middle (beneath the IC) is ground, which is directly connected to two of the pins on the POT. \$\endgroup\$
    – Jerry Dodge
    Commented Apr 7, 2018 at 1:18
  • \$\begingroup\$ there is a diagram of the exact pot that you have ... tough time figuring out which terminals to use tells me that you did not look at the page \$\endgroup\$
    – jsotola
    Commented Apr 7, 2018 at 1:19
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    \$\begingroup\$ Pot isn't an acronym and doesn't need to be capitalized, by the way. \$\endgroup\$
    – Russell Borogove
    Commented Apr 7, 2018 at 1:28

1 Answer 1

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Each triple of pins should be (input signal, wiper, ground). Wiring signal to wiper should give the full signal with no attenuation, and you can ignore ground (or wire a 10K resistor between the wiper pin and the ground, which will be more exactly what the pot would be doing). The two triples are of course for the left and right channels. Assuming the connected pair is ground, just wire the other two of each triple together -- the blue bars I've added to your photo here show where your jumps need to be.

enter image description here

The potentiometer's full resistance between the input signal and ground is split by the moving wiper; the split resistance forms a voltage divider that reduces the input signal voltage by a ratio.

If you find that 100% volume is louder than you like, you can wire resistors signal-to-wiper and wiper-to-ground; only the ratio between them matters to the volume, though you'll want to keep the total somewhere in the 10K-ish magnitude (anything between 5K and 20K is probably fine).

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  • \$\begingroup\$ That's what I needed. Unfortunately one of the speakers is buzzing but no actual audio output. I have more to debug now :-/ \$\endgroup\$
    – Jerry Dodge
    Commented Apr 7, 2018 at 2:08

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