Paul,
Sorry to hear you ahve been having trouble with your Beverages!
Ours worked incredibly well last weekend, and W4ZV has convinced me to put
up several more (we already have seven Beverages, and two of them are
phased Beverage-pairs). I had the pleasure of operating on 80M with
Bill this weekend, and we had a blast! 80M sounded more like 20M for much
of the weekend.
Regarding your two wire Beverages, do you use reflection transformers or
the (relatively ineffective) system of grounding one wire and leaving the
other wire open circuited? I have always used single wire Beverages,
located many wavelengths from any transmit antennas and towers and they
consistently work very, very well!
If you reconfigure your two wire Beverages into single wire Beverages, you
cannot expect that they will perform well with only 12 inch spacing. The
coupling between antennas will be severe, and f/b ratio will be terrible.
Extensive Beverage antenna experiments done by Southwest Research
Institute (SWRI) in the 1960s showed that coupling between parallel
Beverages is minimal provided that they are spaced side-by-side by a
distance at least equal to their height above ground. Using this as a
guide, my East and West Beverages run parallel to each other, eight feet
high, and spaced eight feet from each other. They work nicely, with no
apparent degradation. The SWRI research also showed that Beverages can
cross over each other will little affect, especially if the crossover is
well removed from the feedpoint end of each Beverage.
By the way, like you I also remove my Beverage antennas every Spring and
reinstall them every October! Its a huge job installing nearly 100
fenceposts, a mile of #12 wire and several miles of RG-213, but the effort
pays huge dividends in the DX Contests!
73
Frank
W3LPL
donovanf@sgate.com
---------- Forwarded message ----------
To: <topband@contesting.com>
Date: Mon, 25 Nov 1996 12:35:01 -0600 (CST)
From: KS9K Paul Hellenberg <paulh@truline.com>
We currently are using two, 2-wire beverages. We have to take them down
every year and some years the performance is poor. This year, we have
almost no F/B and have done several things to improve it or determine if
anything is wrong, with no improvement.
We are considering going to four seperate terminated beverages.
The question is this: Can we use our old 2-wire beverage supports for
the terminated beverages? They are 10' tall with 12" spacing between
the wires. Will this affect/degrade the performance of two, opposite
direction, terminated beverages?
73 Paul
KS9K@contesting.com or
Paul Hellenberg paulh@truline.com
Tru Line Lithograhing Inc. 414 554 7300 X125
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