[TenTec] [Ten Tec] OCF Antennas - Which commercial antenna is gest?

[k8mp at aol.com]

 Thanks Steve.
A wise man once said "Sometimes it's better to be lucky than good."


Later, Joe


-----Original Message-----
From: Steve Hunt <steve at karinya.net>
To: Discussion of Ten-Tec Equipment <tentec at contesting.com>; k3ndm <k3ndm at comcast.net>
Cc: k8mp <k8mp at 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?