I've read most of the Beverage-related articles on the reflector for the last
year, as well as the Low Band DXing books by ON4UN. Lately, I've seen many
inquiries into "proper" beverage construction. Thot I'd add my experiences to
the Bev data-base. I live on a mountain-side, in a valley, abt 1100 ft ASL.
1800
ft mountains block me from about NE through SE. I have a good shot pretty-much
all other directions, with a very nice shot to the SW. My main TX 160 ant is a
FW loop, 550 ft around, hanging in the vertical-plane, the top abt 100-110 ft
and the lower leg abt 40 ft off ground. I never thot I could use Beverages,
since my property is very heavily-wooded and quite steep. I had read articles
stating that heavily-wooded areas and non-flat ground would work very poorly
for
beverages. Nevertheless, I was encouraged to try them by Walt, AJ6T and Garry,
NI6T. A few years ago I strung an insulated, #14 stranded copper wire from my
shack, downhill, as far as I could run it and stay on my own property, abt 500
ft. It runs NE/SW. It was not terminated nor matched using any transformer. I
didn't use any fancy poles or inulators, instead just using the existing trees
and shrubs as supports. No magic height, either, just threw the rire over
convenient limbs. It is abt 20 ft high toward the center of the run and tapers
down to the ground at both ends. It performed miserably! Was no better on rx
than my loop. So then I tried terminating the far end in a 450 ohm resistor,
and
built and installed a matching transformer at the feedpoint, but still got vy
poor results. I never heard any signals to the NE, which is EU and AF from here
in central CA. Later, I removed the terminating resistor, and it made a dramtic
improvement in rx signals from the NE and I was later able to work my first EU
stns using it on RX (Winter 95/96). Encouraged, I installed a shorter,
unterminated Bev, abt 250 ft, across the narrow part of my property, running
NW/SE. It seldom hears as well as the NE/SW bev, but on several occasions
lately, I've copied SA and XE stns MUCH louder on that Bev, so it's doing what
it should.
I wound my own matching transformers, using design data from ON4UN's book. They
work vy well. I find the Bevs useful up thru abt 4 MHz. I use no pre-amp. I
plan
to install a third Bev soon, running N/S. I'm currently working on a "front-end
protector" circuit to prevent overload problems when I forget to switch between
the Bev and the main ant for TX. Failure to switch back to the tx ant can be
disastrous for the trnscvr!
In summary, I found no reason to pay for special poles or insulating hardware
for the Beverages, just use what you have and make them as long as possible.
They perform very well for me. They helped me work XZ1N on TB this past weekend
for a new one! Hope this encourages more Topbanders wondering if it's worth it
to build Bevs. It is! 73
John Farber, KG6I 113/98
jfarber@sprynet.com
<---- End Forwarded Message ---->
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