: Boom Box volume issue  ( 1414 )

TC Chris

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Boom Box volume issue
« : March 31, 2019, 11:44:29 PM »
I've got a small Aiwa radio-CD-cassette boom box, EX-30, with an odd problem.  When started up, the volume control doesn't work on the right channel.  It's just loud ad won't turn down.  It works on the left channel.  Eventually, when it "warms up," the control starts working and I can reduce volume.  I was using for CDs in a marina boat barn this weekend and luckily I was the only one working in the big building.  I could let it play away until it decided to work properly. 

Last year, when the problem arose, I took it apart, saw nothing amiss, tightened the various grounding/mounting screws on the circuit boards, and when I put it back together it worked.  I took full credit for a brilliant repair.

Any ideas on what would make a volume control not work until the device has been running a while?  I have no schematic.  What comes to mind is maybe an aging electrolytic cap that re-forms in service?  There's no crackling or intermittence to suggest a dirty control.  I hate trouble-shooting without a schematic!

Chris Campbell