[RFI] Does anyone recognize this RFI?

K9MA k9ma at sdellington.us
Wed Apr 15 14:48:08 EDT 2020

Ah, but they ARE drifting! I don't think the resolution in this image is 
good enough to see the modulation.  The switching supplies I see usually 
are spread out over just a couple kHz.


Scott K9MA

On 4/15/2020 12:27, Jim Brown wrote:
> On 4/15/2020 9:48 AM, K9MA wrote:
>> Looks like a switching power supply running at 55 kHz.
> Unlikely. SMPS are free-running, modulated by noise, so they are 
> "humps" of noise that drift. These signals are stable in frequency 
> with no modulation.
> 73, Jim K9YC
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi

Scott  K9MA

k9ma at sdellington.us

More information about the RFI mailing list