I put up the two wire beverage described in W1WCR's book. It was 400' long
(too short?) and 10' above ground with the last 60' of both ends sloping
down to the ground. I was disappointed with the front-to-back of the antenna.
It seemed to vary wildly with the arrival angle/polarity of the received
signal. Depending on QSB, etc. it would have anywhere from zero to 20db
of FB. One AM broadcast station that is directly off the back of the beverage
(25 miles away, 500' lower in elevation) was actually 10 db better off the
front than the back. When a snowstorm with lots of QRN was moving into the
area, from directly in front of the beverage, I saw about 6 db FB on the QRN.
I took great care that the transformer and reflection transformer were
wound properly. I had 3' ground rods at each end. I never got around to
trying the null steering because I didn't figure it would work any better.
Will be interesting to see if Tim's somewhat longer bev will work better.
BTW my beverage was 400' from the nearest structure.
I ended up with single wire beverages terminated in the normal manner (can
you say "lots of coax"). They have a solid 20+ db FB on 40/80 and about
10 db on 160. At lenghts from 400' to 500' I think they are too short
for good FB on 160. I have been told that running the insulated wire
under the beverage isn't necessary, but wasn't told the reasoning for this.
Despite the fact I didn't get as much FB as I would like on the two
wire beverage, it was MUCH better than no receiving antenna at all.
Perhaps, for me, just a bit better than a unterminated beverage.
73, Jay K0GU jayk@fc.hp.com
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