On Monday, October 12, 2015 at 6:00:31 AM UTC-4, Nick de Smith wrote:
Hi - I have an old-but-very-good-condition SOny CFD-44 rado/CD/Casstte player - been reliable for many years... Extremely well made unit - do NOT want to scrap it unless forced

Recently, every so often it won't stay turned-on - when it's off, you press the power button and the red power LED comes on for maybe 0.5 seconds - a very small "pop" from the loudspeakers, and it then turns off - normally, a light press on the power button and it stays on fine - the power button is a momentary-press push-button, not a latching switch, so its not that.

When its fine (90% of the time) it's an excellend radio cassette...

Bit puzzled as to where to go next...

Thanks

First, the disclaimer: I am not familiar with that unit.

Now the two alternate diagnoses:
a) If a capacitance-start (solid-state contact-start switch), replace the capacitors as already noted. It might not be a bad idea in any case. And don't stop with the main filters, look to any caps in the starting circuit. Such switches may also operate a small reed relay or solid-state relay. If a reed relay, it may be worn out and not holding. If an SS relay, see caps, above and elsewhere.

b) If a mechanical switch, look for dirty contacts, a slipped or worn-through contact or similar. Can you jumper the switch and have it operate normally?

As I remember, and, for the record, that little pacific-rim audio equipment that I own is all Sony or Yamaha, Sony does like solid-state switches as they are much easier to manage with remote control, so I expect that this will devolve to a capacitor problem.

Best of luck with it.

Peter Wieck
Melrose Park, PA