My Beogram 4002 has started to exhibit some speed instability (slowing) during play.  It doesn't play steadily slow, but seems to fluctuate, slowing slightly (but very audibly) then returning to normal.  I eliminated belt slippage or motor capstan slippage as the problem, so it seems that its some poltergeist in the electronics.  The innards of the deck look absolutely unmolested, and there are no visible clues as to the source of the problem.  I don't mind replacing caps or other electronic components, but I am hoping to get some direction on where to start.  Any help or advice will be much appreciated.  As would words of encouragement.

Cheers,  Kevin

Words of encouragement I cannot offer you.  Sorry.

What I can tell you is that the symptom you describe is what happened with my BG4002 a few months ago.  See this thread.

The ultimate cure was a new motor professionally installed.

Good luck!

Could be the potentiometers, relay contacts or capacitors probably in that order. Could be the motor. Have you tried a drop of oil but obviously make sure it doesn't contaminate the belt.. How did you eliminate the belt by any chance?

Thanks for the reply and suggestions.  I changed the belt and cleaned the platter rim and capstan, so I am pretty confident that belt slippage is not the cause.  I'll take a closer look (and listen) to the motor, add a drop of oil as a precaution, and clean the contacts.  I'll let you know how it goes.

Kevin

Be sure and exercise the pots while you're in there, too.