[Elecraft] K1 freq shifting

[Ron D'Eau Claire]

Bring a magnet to the side of the K1 case and you will notice a change
in frequency also.  It acts as a sort of "fine tuning control"  ;-)
73 David G4DMP

Which is also why it's important to keep the K-rigs away from large
transformers. When I first put my K2 on the air I got several reports of
hum on my signal. In spite of my call, that didn't seem right. It turned
out that I had put my K2 on top of my linear power supply and the
magnetic field from the power transformer was modulating my signal. 
Ron AC7AC
K2 # 1289