Switch-mode noise?

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Switch-mode noise?

Post by JEL » Wed Jan 08, 2020 11:32 am

Is this 'switch-mode' noise?

'Switch-mode' noise as in; Some kind of device turning itself ON and OFF continuously, causing the 3 thin vertical lines on the spectrum.

It's not 1 single frequency, but the 3 thin lines as you can see.

However, when the 3 thin lines are thought of as 1 signal (For example, a modulated signal with 3 tones), then it's frequency-consistent (Meaning; it does not drift up or down but always pulses at the same frequency)

When listened to in SSB modulation it sounds like a fog-horn that comes ON and OFF.

The pulses are mostly the same length, but sometimes a pulse or pause is shorter or longer than others.
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