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Re: Topband: Best Height Above Ground for a Beverage RX Antenna

To: topband@contesting.com
Subject: Re: Topband: Best Height Above Ground for a Beverage RX Antenna
From: Earl W Cunningham <k6se@juno.com>
Date: Thu, 11 Jan 2007 12:28:13 -0800
List-post: <mailto:topband@contesting.com>
Jim, K9YC wrote:

"My Beverages are up around 8 ft so that they clear the deer.  They're
good on 160, OK on 80, and almost useless on 40."
==========
Before neighbors encroached, I had five Beverages up in "critical"
directions (EU, ZS, LU, ZL/VK & JA).  They varied from 550' to 1100' long
and were all 7' high.  They were all made of #17 AWG galvanized electric
fence wire, and all had an extremely good F/B, F/S and S/N ratio on 160m.
 All were terminated with a 330-ohm resistor, the value of which was
determined by walking down the wires measuring field strength while a
slight amount of RF at 1830 kHz was applied.  The soil conductivity here
in the Mojave Desert and "poor".

I remember that, during one all-band CW DX constest that after sunset in
JA that the JA's caused severe QRM to the EU stations on 40m while using
my 40m 2-el 402BA beam for receive.  When I switched to receive EU on my
EU Beverage, the QRM from JA disappeared and I had no trouble copying EU
on the Beverage.  So, in my case, the Beverage(s) were quite useful on
160, 80 and 40m.

Once I replaced my longest (1100' on ZL/VK) Beverage with solid copper
#16 AWG wire, expecting an improvement in the performace of that antenna,
but I was dismayed to find that its F/B, F/S and S/N were nowhere near as
good as with the galvanized wire.  Therefore I always recommend using
galvanized wire for your single-direction (non-switchable direction)
Beverages.

As development (neighbors) of my area required that I remove all of the
Beverage wires,  I still "sneak" a temporary one in now and then.  This
really paid off one time when I installed a 550-footer 2 feet high to
snag VK9YY on Cocos-Keeling which could not be heard on any of my other
antennas.

73, de Earl, K6SE
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