Dan,
I've got a couple 260ft terminated Beverages that are abt 5ft high.
Several weeks ago, Earl, K6SE, was nice enuf to do a little analysis with
EZNEC. What he discovered was that a 260 BOG (Beverage on the ground) had
a better F/B than the 5ft high Beverage (40 vs 25). The elevation patterns
were pretty close, 40.1 degrees for the BOG and 41.8 for the 5ft. So this
past weekend, I did a little experiment.
I put a BOG abt 10 ft from the 5ft high one. They both were pointing NE
(from VA). At both ends of the BOG, the last 10 ft or so ran over to
where the 5ft high ant was so I cud use the same gnd rods (I don't know if
this setup was valid to get a meaningful comparison). Both were fed with
50 ohm coax into a standard 9 to 1 Beverage transformer (2 different pieces
of coax and 2 different transformers-yea, I know this wasn't a good match,
but it was either that or nothing). The BOG was terminated with 184ohms
and the 5ft one with 276 ohms (this is what Earl's model suggested).
The noise with both ants was the same on the mtr, abt s1, but the BOG
sounded a little quieter. A NY stn sounded a little better on the 5ft ant,
but I cud not tell any difference between the ants when listening to a GW
stn, which I cud barely hear.
73, Fritz K4OAQ
k4oaq@mindspring.com
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