ROWE / AMI R-93 Combostar Volume Control - All or Nothing - SOLVED

[softcon]

I recently acquired a used ROWE/AMI R-93 ComboStar jukebox.

I managed to get all the mechanicals working and it plays 45s without a problem.  However, the volume control on the back does not work properly - it is either at its loudest or producing no sound at all.  The slightest downturn of the potentiometer will shut off all sound.

Please see the attached photo.  Is it possible that the volume pot has simply gone bad and needs replacement?  If so, does anyone know the specs for that pot?

Thanks in advance for your help!

[Ken Layton]

If I recall, the "volume control" connector on the amplifier can be accidently plugged in backwards.

Always check for bad solder joints on the amplifier circuit boards, especially at the connector pins.

There also should be a preamp jumper plug plugged into the amplifier. Make it is present and plugged in the right way. This is also a connector which can be accidently plugged in backwards.

The circuit boards in the amplifier likely need to be recapped since they are nearly 40 years old.

[softcon]

Thanks Ken!

Interestingly (and perhaps revealingly?), reversing the volume control connector had no discernible effect.  Volume remained at peak, and the slightest downturn of the pot resulted in silence.

I checked the other jumpers and connectors and all seem to be okay.  I'm not skilled or experienced enough to recap, so I will first try a new 10k audio potentiometer. 

[softcon]

After cleaning the volume pot with a contact spray failed to correct the problem, I cut out the 40-year old pot and replaced it with a new 10k volume pot.  Problem solved.