Bob: the stinger is insulated from the tower top and is connected via a wire
down the center of the tower to the tower base. I believe that the shunt
capacity between the wire and the tower surrounding it changes the resonance
point on 80m. I use hightowers on 80m only and connect the stinger to the
tower top. The stinger must be extended considerably to resonate on 80 when
you do this. The SWR bandwidth is much wider, a real help when you work both
ssb and cw on the band.
73, Dan, N5AR
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
Behalf Of Bob Maser
Sent: Monday, May 02, 2005 10:55 PM
To: AMPS
Subject: [Amps] HyGain HyTower Question
This is COMPLETELY off the subject for this amplifier group but you guys
always amaze me as to how much intelligence is dialed in so forgive my
question. I am building a heavy duty version of the HyGain Hytower vertical
and I plan on using it on 160,75,40 and 20 meters. It will be capable of
handling my 3X3 amp(see, it is an amp related topic). My dilemma is that
Hygain says that the combined length of the aluminum stinger and the wire
coming down inside the tower will act as a 3/4 wavelength radiator on 20M
AND the same stinger plus the wire will be a 1/4 wavelength on 75. How can
this be? 234*3/14.2 = 49.4 feet 3/4 wavelength on 14.2. and 234*1/3.8 =
61.6 feet 1/4 wavelength on 3.8. They aren't even close to each other.
They specifically say that the stinger and the wire coming down thru the
tower are used on both bands and there are no stub decouplers used for
either 20 or 75. On the other bands they do use decoupling stubs to get it
to resonate as a 1/4 wavelength.
What am I missing here?
Bob W6TR
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