Topband: 160m noise

[Sinisa Hristov]

Jeff Maass wrote:

>       So, who has *practical* advice of how to apply a choke
>       for flag/pennant antennas? I've been winding 15-20 turns
>       of RG8X in an FT240-77 core.


With high imepdance antennas one needs much better
chokes than with 50-Ohm antennas. I would recommend
winding RG174 (or even smaller coax) on FT240-43.
You must wind enough turns to position the parallel
resonance of the choke near 1.8 MHz. You may need
several attempts to get to the right design.

Winding it without measuring it is pretty useless.
I've described the method of measurement in another
message on this reflector few minutes ago.


73,

Sinisa  YT1NT, VE3EA