On Fri, 10 Dec 2010 04:55:21 -0800 (PST), "
wrote:


I was reading about an Off-Center Fed Dipole (OCFD) antenna.

The following statement was made:

"An effective balun can be made by coiling up coax providing it is
self-resonate at or very near the operation frequency"

In the above statement, what does "self resonate" mean?

Lee KA0FPJ


It means take the coax feeding your OCF dipole and, at the end where
it attaches to the OCF balun, wind it into a coil about 6 inches in
diameter, 8 turns, tape it together so it doesn't uncoil and run the
rest of the coax to the rig.


Check out this diagram -- the guy calls his a "choke balun" -- 6 turns
of coax, 100 mm diamter turns.
http://www.vk3eg.org/technical/xlwindom/xlwindomhtm.htm


This balun is designed for use with and OCF dipole -- it has a
built-in 1:1 balun -- no need for a coax balun (coax choe) as it's
built into the balun.
http://www.balundesigns.com/servlet/...4-cln-1/Detail


Here's one guy's decription of how he built an OCF dipole using the
above balun:
http://w4hh.org/station%20antennas.htm


This guy uses 6-7 turns of coax, 6 inch diameter, as a coax
balun/choke.
http://hamradionation.com/document.p...for-40m-to-10m