Alright already, Thanks for all the humorous emails on a slow wire 100ft
Beverage. Add me to the list of Eznec fools.
When I downloaded EZNec Demo, phased two mini adcock arrays together on a 20
ft boom, Eznec shows azimuth & elevation patterns very similar to those of
two 450ft long Bevs, separated by 325 ft. But expert advice (and I thank
them for it) says that once feeder lines are connected at the feedpoints,
these beautiful patterns disappear.
Some late developments (see AMRAD) using JFET follower reactance matching
preamps can take care of the several thousand ohms of capactive reactance of
these short vertical dipoles, for broadband operation, but then there is
still the metallic leadins, blowing out the patterns. Resistor loaded loops
inherently have much too high and wide a pattern for directional receiving.
So where does that leave the non-Beverage, city lot Topbander ?
I guess I can see the day where someone applies the JFET follower active
antenna tuner/preamp to the feed points, then uses a non-metallic fiber
optic cable for the lead-in. But due to all the folklore & QRM surrounding
the mini-Receive antennas for Topband, I am now almost convinced it would be
easier to just sell out & buy the farm.........Antenna Farm, that is!!!
73, Doug / NX4D
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