I have done a little experimenting with short, single wire beverages, both
terminated and unterminated.
I have two beverages - the NW/SE one is 300 feet (very short) and the
NE/SW one is 450 feet. At the feedpoint, I have a single 4 foot ground
rod. I find that unterminated, they aren't worth the effort, compared
to listening on my xmit antenna. I rarely get much S/N improvement off
the front or back, compared to listening on the xmit antenna.
When I terminated them, thru a 330 ohm resistor to
a 4 foot ground rod, the attenuation off the back of the long
beverage was at least 20 dB on 160 meters. I was ready to take down
the short beverage until I terminated it. Now it's worth having.
Strangely enough, I find
the improvement in S/N ratio to be more impressive on 160 than 80.
Perhaps this just says that my shunt-fed tower is an EXTREMELY noisy
receive antenna on 160, compared to my 80 meter quarter wave slopers.
By the way W0ZV, who seems to hear extremely well, has nothing more than
terminated, 600 foot, single wire beverages, with ground rods at each end.
73,
Steve, N2IC/0
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