Rock Ola sound volume problem

[albertb]

I have a Rock Ola 454 that was playing without problems. But after a year of not being used I encountered a sound volume problem.

When playing a record the jukebox plays full volume, (real loud!).

Turning the volume knob in any direction does not in any way effect the sound volume.

I have replaced the potmeter assembly (P1), but the problem still exists.

I suspect a fault in the capacitor board, but I don't know what to look for.

I could replace all capacitors, but I am not sure if that would solve the problem.

Any hints where to look at or what the culprit might be??

I have the service manual and parts list.

Thanks!!

Albert

[jukenorman]

Hi Albert,
I think that you may have lost the ground to the volume potentiometer which of course is common to both channels. Look at the amplifier schematic - the ground connects to the volume control socket connection 4 and goes to the potentiometer via the cable shield. You'll need to trace it through to find the break or bad joint.

Norman.

[albertb]

Thanks Norman,

That should be easy to find with a multimeter.
I'll keep you posted.

Albert

[albertb]

Am I correct if socket 4 is the socket on the 1 o'clock position (seen at the front of the amplifier?
(1 = at six o'clock, 2 at 9, 3 at 11, 4 at 1, 5 at 3 and six in the center)?

Albert

[jukenorman]

Yes you are correct!

Norman.