A couple of weeks ago, I received the bad news that my neighbour who lets
me run a Beverage onto her land had decided to move house. This meant that
the Beverage had got to go!
Its last serious engagement was the recent Stew Perry TBDC, in which it
often made the difference between reading a signal or losing a contact in
the summer atmospheric noise.
However, in its place, I have run another 'Stealth' Beverage which runs in
the same general direction, in a piece of public bush that lies adjacent to
her land. Where as my old 440' Beverage started off about WNW to ENE and
slowly veered in a slightly more southerly direction as it went onto her
land, the new one is about 60' shorter and holds the line WNW to ENE.
The only other physical difference between the two antennas is that the
last 180' or so of the new Beverage is made up of very thin black
plastic-coated hook-up wire - about 26 gauge and consisting of only a few
very thin strands of copper wire - in order that it is as invisible as
possible.
To my disappointment, the new Beverage (which actually consists of the
first 200' of the old Beverage) seems to give a noticeably lower output
than the old one and is hardly ever a better Rx antenna (in terms of signal
to noise) than my inverted vee dipole Tx antenna.
I am somewhat surprised at the difference in performance between the two
antennas and have put it down to the missing 60' or so in length. I am
also a bit concerned about the continuity of the hook-up wire on the new
Beverage, particularly when it tightens in the wind.
What do people out there think? Could my loss of signal/performance be
down to the reduction in length, poor continuity in the new Beverage end
section, or are the other factors I should consider?
At the moment, I have not looked at the matching of the new Beverage, which
is fed with the same 9:1 homebrew matching xfr as the old one, but I guess
checking/improving this could be an idea...
Both the old and new Beverage are unterminated. Signals on the new one
seem down in both a westerly and an easterly direction from the old one.
One interesting thing is that the new Beverage seems to work as well as the
old one did on 80m (output and s/n ratio-wise), making me think that for
some reason the new one is somehow too short for 160m.
Any ideas would be appreciated.
Vy 73,
Steve, VK6VZ
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