Re: Unresponsive volume control

GD
 

Braden, looking down on the QCX with the control in the bottom left corner the right hand control pin should be at ground. It should measure zero ohms from this pin to ground.You say that you can vary the resistance of the control. The middle pin is connected to a wiper that sweeps around a carbon track inside the pot, this carbon track is connected to the Left and Right pins with the Wiper decidingĀ  the selection of resistance neededĀ  for audio control. This applies also to the Right pin, Checking this varying resistance with the pot in situ gives a false confidence. You could remove the pot, measure across Right and Left Pins, confirm there is continuity, measure the Wiper centre pin to Left and Right pins. If the internal carbon track is not connected under a crimp you could remove the pot casing and have a look. Bear in mind you installed this pot by tightening it to the PCB with its nut and washer so did you make sure the pins were aligned to PCB holes before fixing and not put the 3 pins under strain?

73 Geoff G4CAO

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