The answer is to run everything on direct current. Nicola Tesla was right.
Calling Elon Musk! -- business plan! Next, we ban lightning; no more pesky
atmospherics!
On 11/1/2022 3:38 PM, kq2m@kq2m.com wrote:
The other type of noise was what I'll call a "Squiggler" which was loud and
about 3 - 5 khz wide.
Hi Bob,
You may be hearing high order harmonics of the square waves in a switch-mode
power supply (SMPS) which are ubiquitous -- there are at least a couple of
dozen in the typical US home -- or some power control electronics, like a
variable-speed controller for a motor.
Study this applications note, which ran several years ago in NCJ as a
two-parter.
It provides lots of ideas about figuring out the type of noise you're
hearing, how to find the source, and how to kill (or reduce) the noise.
http://k9yc.com/KillingReceiveNoise.pdf
73, Jim K9YC
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