Hello Dan!
The original HyTower was designed for the "high end" of 80 meters (above 3.9
MHz). To use it below 3.9 required the addition of the base inductor.
When I decided to build my 80 meter 4 square antennas out of HyTowers
(stripped of all side stubs) it required extending the 2" section and
several of the smaller diameters of tubing in order to achieve 0 ohms of
reactance at 3.510 MHz. The final total height is 75 feet. The large
diameter reduction from the 24 ft of tower to the aluminum "stinger" causes
the length to be much longer with the HyTower mechanical design than it
would be if the elements were made from #14 wire (the entire length).
Hybrid fed 4 squares achieve minimum power in the dump load with elements
that are self resonant lower in frequency (140 KHz in this case). So the
minimum power is 0 watts in the dump load at 3.65 MHz - with the elements
tuned for 3.510 MHz.
Here is a photo of one of the 80 meter 4 squares using extended HyTowers at
K3LR http://www.k3lr.com/Vertical/MVC-750X.jpg
73!
Tim K3LR
http://www.k3lr.com
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Dan Schaaf
Sent: Tuesday, August 04, 2009 7:16 PM
To: TowerTalk@contesting.com
Subject: [TowerTalk] HyGain HyTower Questions
I am looking to understand how the HyTower can be advertised as a 1/4 wave
antenna on 80 meters. The standard 1/4 wave length at 3.6 MHz is
approximately 65 feet, yet this antenna is 53 feet tall on 80 meters.
Vy 73, Dan K3ZXL
http://www.k3zxl.com
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