[Antennas] RG-178 balun turns count

Fri Jul 2 17:49:33 EDT 2010

Both Jim and Danny are correct. Jim is not trying to
address corner cases like the C pole. I'll jump in here
and ask:
In light of the extremely difficult balun situation and
the relatively narrow bandwidth, why would I even want
to build a C-pole? In most cases, it isn't that hard to
build a 20 meter ground plane, which will be foolproof.
If I were in a restricted area where even that weren't possible,
I would just fall back to my mobile, with a Hi-Q screwdriver
and CB whip (total height 13 feet). Also foolproof and
probably gets out as well as the C-pole and it cannot be
outlawed. Plus it covers a lot of bands. What is the
problem that the C-pole is the optimum solution for?
Rick N6RK
Brian Cake wrote:
> Danny,
>> Chapter 6 of Jim Brown's excellent paper includes only measurements of
> the magnitude of the balun common mode impedance...there is no way to tell
> whether it is all reactive or all resistive or a bit of both.
>> In the section titled "The Dissipation Question" he states "the worst
> case puts the full transmitter voltage across the choke under the
> condition
> of infinite imbalance". This is absolutely not the worst case for antennas
> that are fed off-center, where the common mode voltage can be many times
> the
> feedpoint voltage. This is the condition that exists in a C pole and any
> OCF
> antenna.
>> These are also my last comments. Nice doing battle with you!
>> 73
>> Brian KF2YN