Frank Dresser wrote:
Did they play those tones and then break into the "Propeller Airplane Sound"
from time to time?

Funny you should use that comparison. The first time I ever listened to
SW was at the house of a friend who had just got the radio and didn't
know a thing about it. Not knowing about Soviet jamming stations, every
time we passed one all we could imagine was that it was ignition noise
from a propellor airplane somewhere. This was waaay back in the day of
the buzzsaw and before sophisticated jammers like bubble jammers.

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