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Michael Ware
 
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Default Hum on Optimus STA-20

If you are talking about a Realistic STA-20, I might be able to hook you up
with a service manual.

Mike

"Sam Goldwasser" wrote in message
...
This is a nice little low power receiver.

The problem is an annoying low level hum present at all volume levels
and all sources. I tested the two main filter capacitors for uF and ESR,
and paralleled each one with a good capacitor with no no apparent change.
Are there other power supply filter caps?

The hum is still present with nothing attached to the receiver except one
speaker.

A schematic or suggestions appreciated.

Thanks.

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