[Elecraft] Choke for QRP with unbalanced antennas?

[Julia Tuttle]

Hi folks,

I was tinkering with a whip + counterpoise antenna connected to my KX3 by a
short stretch of coax with BNC connectors a couple nights ago, and
discovered (painfully) that there was quite a bit of RF coming back along
the ground when I bumped the outside of the antenna connector. I know from
experience that the KXPD3 can end up tingly in turn, and I'd like to avoid
that.

If this were a fixed antenna, I'd just slap one of the LDG RU-1:1 ununs on
it as a choke, but they're pretty chunky -- they're rated for 100 W CW, and
have SO-239 connectors, which would require adapters on both sides in this
setup.

Does anyone know of a choke more appropriate for this kind of setup? I'd
prefer something smaller (rated for maybe ~40-50 W continuous?) and
natively BNC, so I don't need to juggle adapters.

More broadly, is this the appropriate way to fix this problem? This was
with the counterpoise extended as best I could, and with the radio powered
from mains (which may have actually made the problem *worse* by providing a
more attractive path than the counterpoise?).

(As an aside, when components like baluns/ununs or tuners are rated as "100
W CW, 200 W SSB", do they mean literally a continuous wave, or do they mean
CW at a standard Morse duty cycle of roughly 50%?)

Thanks and 73,

Julie