Topband: Elimination of Treadmill RFI on 160 meters

[Richard (Rick) Karlquist]

On 1/29/2015 10:23 AM, Carl Clawson wrote:
> Nice to hear all the comments, recommendations, and indeed some success
> stories here. I too have a treadmill problem. Although I'm blessed with a
> radio-friendly spouse who always asks before she starts it up, I'd like to
> add a line filter. Ferrites on the cord don't by themselves squelch it.

Ferrites on the cord don't work on 160 meters if they are of
the single turn class:  easy to use, but ineffective, clamp on beads.
What does have a chance of working is 15 or so turns on a 2.4 inch O.D. 
toroid.  Impedance varies as the square of the number of turns, so
15 turns is like 225 beads.  Fair-Rite Products also makes some large
clamp on ferrites that you can wind with a lot of turns.  The advantage
of these is that the plug on the end of the cord is no longer a
constraint.

Rick N6RK