Comments by "" (@rvdb8876) on "Russian Woodpecker - The Radio Signal That Wreaked Havoc Around The World" video.

As a Belgian radio amateur I remember that annoying sound very well. The signals were sometimes so colossally strong that if you worked in SSB, the slow automatic gain control completely suppressed the station you were in QSO with. It was all over shortwave and I also think they didn't put much effort into using lowpass or bandpass filters. Because often the signal could also be found on the first harmonic of the frequency at which you heard the woodpecker. This was a plague that has made many HAM operators very annoyed.
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