I used one on topband for a couple of years. For DX it usually worked better
than a dipole at 50'. With the base loading coil to resonate it on 160M, it
is still worked on 10, 15, 20, and 40M, but not on 80M. You must change the
tap on the coil to resonate it on 75 and on 80M a different parts of the 160
band. My MFJ antenna analyzer sure comes in handy for finding the correct
tap. From memory, my 2:1 SWR bandwidth on 80M was about 150 KHz and about
50 KHz on 160M.
The main problem with the baseloaded Hytower on 160M is that you can not run
much over 100 watts without burning out the insulators. I know. I did it
with about 200 watts. Wrapping the stock insulators with a thin insulating
teflon tape, it took 500 watts to burn out the insulators. Did that, been
there.
With 100-200 watts, I worked about 50 countries over a 2 year period on 160M.
As K0HA writes, your installation (particularly your radial system) will
determine how well it works. I added random length radials (on the ground)
for several years whenever I came across cheap wire.
My present 90' top loaded, 160M shunt fed tower, with a similar radial system
(several thousand feet of wire) is about 6 dB better than the Hytower on
transmit and receive. I used the A/B test for about a month several years
ago to determine that. I also had a slopping FW loop (averging 40' above
ground and slopping down a 30 degree hill to the east) that was occasionally
as good as the 90' tower (never better) especially to the east. It was often
better than the Hytower.
Besides the Hygain Hytower base coil (you can make a better one out of 1/4"
copper tubing) Hygain still sells a accessory to convert the Hytower to 160M
(full power) with a 40M choke (I think it is) and about 100' of wire which
creates an inverted L. Since the vertical section is the 26' tower section
of the Hygain Hytower, I think you can probably make youself a better
inverted L (more vertical section) with wire and some telescoping tubing or
even a tree.
I think the Hytower in the clear with a good radial system is a superb
antenna on 40/80M, very good on 20M, and good on 10, 15, and 160M.
Doug W0AH
--
FAQ on WWW: http://www.contesting.com/FAQ/topband
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|