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[AI5BC]

I have tried isolating the RFI by turning off my circuit breakers and have found that with all the breakers off my noise goes down to about s-1 to s-2 on 40 and 20 meters.

Suggestions?

OK you are the source of the noise. Now go find it. With all the breakers turned off, turn them on one at a time to find which circuit or circuits are causing the noise. If I had to guess, the problem child is on the same circuit breaker your radio is using. Something like a laptop, TV, wall-sort plugged in upstream or downstream on your branch circuit. That is why you should use dedicated AC circuits.

If you have any kind of grounds in the shack, disconnect them and see what happens.

[KH6AQ]

The procedure to find the offending device(s) in your home is:

Switch circuit breakers OFF/ON to find out which room the device is in.

With the power to that room on, unplug devices in that room one at a time to find the RF noise source.

You might find several sources. RFI can be like peeling an onion; remove one RF source and the next lower one is revealed. You might want to check all bands carefully, record the S-meter readings and get to work. After fixing one noise source you can look for others. Enjoy!


In my small house I located eight RFI sources.

Water catchment UV lamp water treatment: wrapped the AC cord around an FT240-31 ferrite. Fixed.

Four USB charger wall warts: replaced with a different brand. Fixed.

Two ceiling fan lamps: leave lights off when operating. Fixed.

Router: Wrapped the Ethernet cables 12 times through an FT240-31 core. Wrapped the DC cable 12 times through an FT240-31 core Fixed.