[CQ-Contest] CQWWSSB weird noises on 10 M and other bands

James Cain jamesdavidcain at gmail.com
Wed Nov 2 10:51:14 EDT 2022

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

On 11/1/2022 3:38 PM, kq2m at 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
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.


73, Jim K9YC

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