Bought a home stereo system online for $20

Hi all! My stereo system motor hums and whines loudly when the volume and bass gets turned up (at least I believe it's the motor). Any ideas of what it is or what I can do? BTW, I am very grateful for internet tech wizzes, you are the greatest!

by Philipsmmr
September 27, 2018

Possibly a ground problem. Look up hum loops.

by mikerogerswsm
September 27, 2018

Hi. It isn't caused by my cable TV outlet, I unplugged that, it didn't go away. It hums on FM (doesn't pick up AM) too. I read something about whether it occurs before or after the sound is amplified, but couldn't dig any info on how to find out. Thanks.

by Philipsmmr
September 28, 2018

If you would care to identify the unit we can get hold of a manual and view the schematic. Some further information would help. When did it start humming? Did it come on slowly/suddenly/always? How old is the equipment? Does the innards look like new or has it been modified? Unplug before looking inside! Did the previous owner have the same problem?

by mikerogerswsm
September 28, 2018

RCA RT2760. I bought it last week, and realized right away that it would hum (through the reciever) at high vplume/bass. The lady told me it was from 2000s, probably mid to late. She didn't tell me there was anything wrong with it. Thanks so much.

by Philipsmmr
September 29, 2018

The manual is here:

It may give some useful information on the proper hook-up. If you can get it going it certainly is a bargain.

You may need to get a local expert to show you how to replace the bigger electrolytic capacitors.

Good luck. mike

by mikerogerswsm
September 29, 2018

Hey Mike, thanks!

by Philipsmmr
September 29, 2018

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