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.
73,
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@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
--
Scott K9MA
k9ma@sdellington.us
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|