[Hallicrafters] "Airplane" Noise on Short Waves; was: Why I'm a Hallicrafters Guy

[Marshall M. Dues]

Back in the '50 I lived in a little village of Pine Run, Michigan, about 
12 miles north of Flint, Michigan.  Before I became a ham, (novice call 
was WN8DIM), I did a lot of short wave listening on the family living 
room Philco floor radio that had several short wave bands (and between 
two and three million knobs - of which only four actually did 
something!), and I remember the famous "airplane" noises.  I really 
thought I was hearing airplane engine/propellor noise while in flight, 
but later learned what I was actually hearing were hospital diathermy 
machines.  Back then, diathermy machines were medical instruments that 
used short wave radiation as a source of heat for the local heating of 
bodily tissues for medical purposes.  They also radiated across the HF 
spectrum not unlike the old spark gap transmitters of yore!  But it sure 
did inspire a young boy who could not wait to become a pilot and operate 
aeronautical mobile from an airplane, someday.

Regards,

Marshall Dues, WB5MYO/Aeronautical Mobile
Van's RV-6 homebuilt sport plane N243MD 899 hours on it as of Sunday!


David Hollander wrote:

> The airplane noise I am referring to was not the woodpecker. I remember 
> the woodpecker too well tearing up 20 meters while trying to work DX 
> over the pole in the evenings.
> 
> Would still like to know what it was. It sounded like the continuous 
> roar of an airplane engine.
> 
> Dave N7RK