It must be that we are coming into a contesting and dx season at the sunspot
minimum, since there has been alot of talk recently on beverages on both
AA6TT's 160 meter reflector, and on this reflector. Amongst other
conclusions there , the most important was to not use steel wire. The reason
is, because of its high resistance - especially at radio frequencies, and
for permiability factors, it destroys directive possibilities that can be
achieved by low loss wire - preferably copper of reasonable diameter.
At N2RM during the past contest season, a highly effective system of european
phased beverages were put up by WM2H and KZ2S. Sal, WM2H (our 75 meter
operator) insisted that John, KZ2S (alias, Sluggo) make numerous modeling
efforts to design a system with optimum length and spacing for two beverages
to be used on 75 and 80 meters. The particular emphasis was to reduce high
angle lobes towards Europe. Because of John's design efforts, the antennas
are referred to as:
PHASED SLUGGOS
With Transit in hand, and steel poles with fiberglass rods attached in hand
to be used where trees were unavailable, a pair of 500 foot long straight
beverages were put up. They are spaced 200 feet apart and aim at the heart
of Europe - 45 degrees. No. 10 copper wire was used as to not compromise
the pattern, and as W3LPL commented in his earlier message, both the feed
point and termination end were sloped gently towards the ground to make for
the best pattern. The length and spacing of the beverages is probably
different from Franks design because the emphasis was to try to minimize the
higher angle lobes off the front of the antenna.
Sal did talk to W3LPL about the idea before putting up the antennas up, and
got some encouraging words from him, but I don't think Frank put his up until
he heard how well they worked at N2RM.
In a few words, they are quiet, and really seem to work, on both 80 and 160
meters.
If anyone wants to e-mail Sal, WM2H about this project, he can be reached at:
SAA8618@AOL.COM
73, Bob, N2RM rmoore@doc.gov
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