[Elecraft] Heil ProSet Headset as offered by Elecraft

[Jim Brown]

Hi Michael,

Are you sure it's the headphones?  What sort of antenna are you using?  
The current in an antenna creates a magnetic field that can be quite 
strong in the near field. When I lived in Chicago, my best antenna for 
80 and 160 was a long wire that ended in the shack, and it had a current 
maxima at the feedpoint (the shack).  The field shut down the RS232 port 
in my computer sending CW to my K2 using the standard K2 cable with as 
little as 12 watts! That cable used parallel wires. I fixed the problem 
by replacing it with CAT5, using one pair for each of the RS232 
signalling ports. Twisted pairs STRONGLY resist magnetic coupling. Once 
I did that, I could crank my Titan power amp to near legal limit power.

I'm not suggesting that twisted pair is a solution, but I am suggesting 
that, depending on your antenna and its proximity to your aids, that 
field could be getting directly into their pickup from your antenna!

73, Jim K9YC

On 11/2/2018 1:59 PM, Michael Blake via Elecraft wrote:
> When running more than 100 watts on 80 or 40 the RF causes the hearing aids to switch modes randomly when the telecoils are activated by a nearby magnetic field.