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Variable resistor problem.. Answered


I ripped this out of a car audio system, i don't know the input volts, or whats what. I use to have it connected to a 3V battery to change a LED from 0 to 3V. Well, i pulled it out, wires gone. resolder wires as you can see. problem: WHAT IS WHAT?! All i know by the labels is it says RED on the lowest rail. the rest, dont know. If someone can please help me id love that. It switches on/off as well as changes volts. so i need 4 wires connected.


Is this is an audio pot, as well as the on off switch? Is so, it could be a logerithmic pot. Anyway, does any of the information at this LINK help any?

Oh yes thanks! By any chance even though its audio, do you know the voltage rating? I just did 9V and it doesn't smoke or feel warm. it ranges 7, 5, 3, 2, 1, and 0 just about (multimeter)

a car battery gives 12 volts, so thats probably the rated level.

The "on/off" switch would have to be rated for a minimum of 12v. but the pot might not be. An audio pot normally does not need to carry a lot of current. On my of those I have messed with, the on / off switch is isolated from the pot.

i have on like that down in my lab. tore it off an old radio. its rated to 12 volts though.

Ok, I was speculating why, but I guess it is better to be over-rated then under :-) And as he shows with his voltage measurements, it is slightly logarithmic.