Sam Goldwasser wrote:
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?

is the hum 60hz or 120hz? big difference in the causes for each..

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

A schematic or suggestions appreciated.

Thanks.

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