[Hallicrafters] "Airplane" Noise on Short Waves

[Freeberg, Scott (STP)]

Yes I remember the "Woodpecker" over the horizon radar signals very well.  What pain that thing that thing was.  I remember cursing it while in College in the mid 70s'. THere were discussions about hams zerobeating it,  transmitting back 'dits' at the same rate, and forcing it to jump away.  I never knew if that was true or folk lore.

Yeah I know what I was hearing as a kid was the HF Multiplex RTTY signals.  I didn't know what that roar was until I had to listen to it all the time in the background while in the shipboard radio room.  I had to listen to it all the time to check for propagation changes.  It was always a scramble during helicoper operations when the flight deck crew would lower the vertical antennas so they were horizonal to the water instead of standing straight up. Sure made a difference in receive signal :->  

73, Scott WA9WFA