Comments by "Peter S" (@Peter_S_) on "Inside The Shortwave Russian Woodpecker Killer" video.

  1. It appears to not have any actual filtering, instead it uses a 'ring' of capacitors to sequentially store the average DC level of the signal with a new capacitor being used for each 1/10th of a second time slice. As long as the transmitter and eliminator used the same rate, no sync was necessary as the pulses would just happen to line up on the same capacitor with each pass around the 'ring'. This caused the 'ring' to store up the profile of the low frequency pulses, also making them available to replay with inverse polarity. The level on the capacitor for that time slice was subtracted from the raw signal like combining anti-noise in a noise canceling headphone and there you go.
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  2.  @RingwayManchester  Clive doesn't do RF.
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  3. It's a time slice dependent DC level restore. See my post for a brief rundown of the circuit.
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