[EMAIL PROTECTED] wrote:
In a message dated 10/27/06 4:38:23 PM Eastern Daylight Time,
[EMAIL PROTECTED] writes:
The Diamond bottom tube may, (and likely) contains a broad band ferrite
cable choke.
Probably - to keep RF off the outside of the coax. Such a choke would cost a
few dollars at most.
Actually, a choke on the coax would *prevent* the antenna from working
unless it was mounted on a metal mast. It needs a counterpoise and the
coax shield provides it unless a mast or radials are present.
This is actually similar to the 'e-h' antenna, in which the alleged
'antenna' at the end of the feedline serves to tune the shield of the
feedline to resonance. The shield actually does the radiating. Adding
a bead balun to an e-h antenna causes the antenna to stop working and
the balun to get hot! No, I don't want to start a thread on this
antenna either!
In the Diamond antenna, the feedline is only half of the antenna, with
the 22-foot radiator being the other half and the resistor smoothing out
the SWR variations.
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco
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