West Florida Components

How to Clean the Potentiometers on Your Audio Equipment

If you have a dirty potentiometer, you probably will find out about it from the scratchy sounds your equipment will make when you adjust the volume control.

Here’s a simple and safe method to rid yourself of that noise:

-Unplug your equipment
-Remove the cover from the knob
-Carefully use contact spray on the shaft of the potentiometer
-Replace the knob
-Plug your equipment back in and turn it on
-Rotate the knob from one end of the range to the other.

Did that work? It should have – but if you still hear the scratchy noise, you can move onto this step:

-After unplugging the equipment again, remove the potentiometer from the housing and use the contact spray at the base. Before you put it back into the housing, rotate the shaft to be sure that it’s moving cleanly.

If you still hear noise, it might be time to replace the potentiometer. Before you cut the wires, it is recommended that you snap a couple of pictures of the previous installation including all wires leading to the potentiometer. This will assist you greatly when it’s time to connect the new pot.

Once you obtain the correct pot to install, you will need to use solder and a soldering gun to reconnect the wire leads from the potentiometer to the equipment.

Hopefully it won’t be necessary to replace the potentiometer. Most often, a spray is all it takes to rid yourself of the noisy potentiometer.

Potentiometer Basics

A potentiometer is a manually variable resistor. It has 3 terminals, one of which is connected to ground, the second to a current source and the third to a sliding contact that runs along a strip of resistor. The varying resistance is used to control other parameter like volume. Potentiometers are widely used electronic components used in volume control, brightness control etc. though recently they are being replaced by digital control circuits.

A potentiometer can regulate the amount of current flow in a circuit. In this case, the maximum current flow is limited by the resistivity of the variable resistor. The variable resistor can be in the form of a linear strip or a circular strip. In a linear potentiometer, the cross section of the resistor is constant and the resistance varies directly with the length of the resistor. In a logarithmic potentiometer, the resistor tapers from one end to the other and the cross section varies likewise. The variation of current flow is logarithmic in this case and is used in audio amplifiers.

A digital potentiometer is digital equivalent of variable resistor potentiometer. It is a digitally controlled electronic component with built in IC or a digital to analog converter. It is widely used in instrumentation amplifiers. It has limitation of being restricted to currents of a few milli amperes and voltage in the 0 to 5V range.