Thanks Steve.
A wise man once said "Sometimes it's better to be lucky than good."
Later, Joe
-----Original Message-----
From: Steve Hunt <steve@karinya.net>
To: Discussion of Ten-Tec Equipment <tentec@contesting.com>; k3ndm
<k3ndm@comcast.net>
Cc: k8mp <k8mp@aol.com>
Sent: Wed, Sep 23, 2015 7:37 am
Subject: Re: [TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?
Joe,
A possible explanation - and from my experience the most likely one -
is that your "antenna" was actually the braid of your coax, top-loaded by
the OCF wire. The differential-mode impedance of a 130ft wire fed at the
25% point is so high on 160m it's almost impossible for any choke/balun to
prevent CM current on the braid. You'd only need about 30ft of coax for
that system to appear as a top-loaded 160m quarter-wave.
Steve G3TXQ
On 23/09/2015 11:21, Joe Papworth via TenTec wrote:
Maybe you can explain why an ocf antenna I once had worked on 160.
I called it "My accidental 160 meter antenna." It was a full wave on 40, (i.e.
130 ft) and fed with coax, 1/4 wave in from one end. I intended to use it only
on 40 but I discovered it was resonant on 160 also. Any idea why it worked? Or
was it just pure luck?
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