Hi Mark,
I've built countless dozens of Beverages and its absolutely true
that "Beverages just want to work."
About the only situation where they do not work is over highly
conductive soil such as salt marshes and ocean front locations
with salt water saturated sub-soils.
Signals received by a Beverages are normally about ten dB down
from simple antennas like dipoles and verticals. The preamp in
your transceiver will compensate for that loss. If it does not, you
have an undiscovered fault in your Beverage antenna, matching
transformer or feed line.
Do you have an antenna analyzer such as an MFJ-259?
If so, what results have you seen?
73
Frank
W3LPL
----- Original Message -----
From: "Mark Lunday" <wd4elg@outlook.com>
To: topband@contesting.com
Sent: Tuesday, June 30, 2020 6:56:40 PM
Subject: Topband: Some experiments with a short beverage, not succeeding very
well
"Beverages just want to work" is what I have heard.
Not having much luck with that here. I suspect operator/installation error.
I did a lot of reading and I must be doing something wrong.
* 250 feet of insulated wire strung out in 030 degrees direction toward EU,
pretty straight, varying in height from 4 to 6 feet, running through thick
brush with no metal objects or artificial elements along the run.
* 9:1 transformer at feed point with ground rod
* 300 feet of coax, mix of RG-8, MMR-400 to get to the edge of the woods from
the house
* No terminating resistor
On bands 160-40, the signals are very weak. I am monitoring WSPR, FT8. I can
hear signals on 160-40 but they are way down compared to dipoles and inverted L
on the same bands. Like 20-30 db down. From what I read, I should NOT need an
HF pre-amplifier, right?
Signals on 30 and 20 seem to be better and I can copy some DX from EU on FT8.
I will try installing a new ground rod, the old one is 10 years old and perhaps
not making a good ground connection at the feedpoint. The transformer is brand
new, so that's not an issue. The coax has tested out fine. Soil is central
North Carolina clay, a bit dry at this time.
I am guessing performance is poor on 160-40 because of the short length and
that it's bi-directional (no terminating resistor), which I am seeing on 30
meters. But I did not think it would be THIS bad on 160-40....
Mark Lunday, WD4ELG
Greensboro, NC FM06be
wd4elg@arrl.net<mailto:wd4elg@arrl.net>
http://wd4elg.blogspot.com
SKCC #16439 FISTS #17972 QRP ARCI #16497
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