[TowerTalk] AV-640 (was GapChallenger ComparisonTesting Studies)

[Dan Schaaf]

Joe,

Believe what you like. I prefer to call it for what it really is. The AV-640 
is a 3/8 wave vertical with elevated radials ( Counterpoise for those who 
prefer ). It has a balun for impedance matching since it is not 1/4 wave.
I have never seen an antenna that is an off center fed dipole called a 
Windom. If you have seen Windom terminology applied to an off center fed 
dipole, then has it occurred to you that it was named incorrectly?
And please don't tell me that you are an old timer and therefore are 
all-knowledgeable. Old timers have been known to be wrong just as newbies.
I have an "old timer " friend who insists that the old days were better, and 
his knowledge of things as " If it was good enough for my father then it is 
good enough for me". Never thinking that his father might have been wrong or 
out of date compared with today's knowledge.

And all the antennas that you describe do not operate the same way. All you 
can say is that they radiate.


Dan Schaaf
K3ZXL
"In the Beginning there was Spark Gap"
www.k3zxl.com
----- Original Message ----- 
From: "Joe Subich, W4TV" <lists at subich.com>
To: <towertalk at contesting.com>
Sent: Monday, April 26, 2010 12:20 PM
Subject: Re: [TowerTalk] AV-640 (was GapChallenger ComparisonTesting 
Studies)



Dan,

 > Go to the ARRL antenna book and look at a windom. It DOES NOT have
 > a break at the feed point for coax center and coax shield. It is a
 > straight wire with the coax center at the off center point.  The
 > shield is not connected, or else it is a single wire feed to the
 > horizontal wire.

Amateurs have been calling off-center fed dipoles a "Windom" for
more than 40 years.  The oldest ARRL Antenna Book I have owned
includes that same discussion.  Whether you insist on calling only
the single wire fed antenna a "Windom" or apply the name broadly
to the whole family of antennas that operate the same way is not
material ... whether you use a single wire attached at its
characteristic impedance, "balanced" feeder attached at its
characteristic impedance, or coax with a balun attached at the
transformed impedance, the antennas all operate identically.

By the way, even the single wire fed version of the off center fed
antenna is not really a Windom.  Loren Windom only reported the work
of a group of Electrical Engineering students at The Ohio State
University when he was a law student there.  If you want to be
precise in naming the antenna, give credit to the proper persons.
In the meantime, I choose to recognize Windom in the concept of
all off center fed antennas just like any center fed doublet is
a "Hertz" and any end fed antenna against ground is a "Marconi."

73,

    ... Joe, W4TV