Noise Blanking

From HFUnderground

Noise Blanking refers to the process of eliminating repetitive, pulse-type noise from a received signal. "Noise Blankers" became popular due to interference caused by the "Russian Woodpecker" on the HF bands during the 70s and 80s; this was a kind of radar that sounded like a woodpecker when received by a shortwave radio. Noise blanking can also help to remove noise caused by the points in a mechanical distributor in an automobile engine, and other, similar interference.