In a message dated 11/3/01 7:04:04 PM Pacific Standard Time, basalop@gte.net
writes:<<
Though I do not have the data in front of me at this exact moment,
I do remember Ham Radio Magazine did run a number of articles on
the Vee antenna.
"One thing that did stick in my head, was connecting
the terminated ends together with a ground wire."
Besides the use of
radials, out there, by tying the elements together, it made the
antenna much easier to use. This made up for changing ground
conditions. If I remember also, by sloping the legs, it took out
quite a bit of the directional characteristics of the antenna.
I wish I had those articles now, but I know I saved them. I just
need to find them. The antenna has always fascinated me, but I
have never had the room to give it a try.
73 Jim K7SLI
Jim: Could you explain this a bit more. It sounds interesting. Is this a
wire between the bottoms of the termination resistors laying on the ground
between ground rods or what? Why not just run wires from the ends of the Vee
beam horizontally to a single termination resistor in the middle off the
ground. The horizontal distance between the termination resistor has to be
shortened from the Vee Beam wires. There are "Magic Lengths for Vee Beams"
like 555' that are 1/2 WL multiples for all bands. This assures that if
terminated, a Lo-Z is reflected back to the feedpoint on all bands. If a Vee
Beam or LW ends in an insulator or a HI-Z and you have a length that is a 1/4
wave or odd multiple at the lowest frequency, It will be reflect back to the
feedpoint a Hi-Z on the higher harmonic bands. If a Lo-Z occurs on all bands
at the feedpoint of any antenna and the open wire feedline is my Magic Length
or multiple of 134', you will see a Lo-Z at the end of the feedline. In the
Stone Age of the Last Century it was possible to connect the open wire line
and it's Lo-Z load directly to the link and a series Xc to ground and
properly match it on any band just by changing the number of turns in the
link of the tank circuit. You used the link that gave the maximum output for
a given input. It also fed right into the balanced input of the receivers of
the day.
I still have a SX-88, 75A1 (mint) and a Pierson KP-81 (about 1948). These
were the 3 best receivers ever made back then. I want to compare these
receivers to those of today for sensitivity and in pile ups. The KP-81 even
had the Lamb IF Noise Silencer of the 30's. He was on the Staff at QST.
I'll have to try the "Cross Over Termination Connection" in Eznec and see
what it looks like. If it looks good I have a location where I can try it.
I heard back then some one had patent of some kind on the termination concept
and RCA wanted to use it without paying. This story doesn't sound right.
Anyhow whoever wanted to use it without paying royalties came up with another
way to terminate a Vee Beam. They dropped a wire to the ground at the end of
the Vee Beam and then laid it on the ground for about 200'. This seems to
work but it's not a purely resistive termination and can vary from band to
band. There are several ways to compensate for this and/or improve it. At
the ground secure point, running Nicrom wire on the ground for say 200' is
more resistive.
QST had an article on variations of grounded at the end wire antennas I tried
that do work. k7gco
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