In a message dated 4/21/03 9:06:47 AM Pacific Daylight Time,
antennaware-request@contesting.com writes:
> I just bought a cushcraft D40, 40 meter rotatable dipole and want to try an
> alternative to the 12 loops of coax. Can I use an off-the-shelf balun used
> for dipoles? What is the feedpoint impedance of the dipole before the
> balun, ie., should I use a 2:1 or 4:1 balun? Ideas?
Hi, Michael --
This question is better posted to TowerTalk - the tower and HF antenna
construction reflector. Antennaware is mostly for discussions of antenna
modeling software.
To answer your question, any 1:1 balun will be FB. The main problem with
using the CC-type RF choke is that it splits the coax to the feedpoint which
is difficult to waterproof. Also, do not use a foam dielectric- type coax for
the wound RF choke since it'll cold-flow over time whereas a more dense
dielectric (i.e. RG-213) won't.
Cheers,
Steve K7LXC
TOWER TECH
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