You use an infrared light emitting diode and detector. I think there was
an article in QST a year or two ago.
Ken Hopper wrote:
> I am falling love with wireless headphones (Jensen Linx where you use your
> favorite headphones and a belt clipped RX). So how would you go about WIRELESS
> PADDLES for true roaming CW operation?
> de ken n9vv
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