> > He claims that for 1.8 mHz and above, the ground systems at each end
> > of the antenna should be bonded together with an insulated wire lying
> > on the ground directly under the antenna wire for its entire length.
> > This seems contrary to anything else I have ever read about Beverage
If ground is excellent, reduced wavefront inclination deminishes signal
strength received. A steel wire(s), or coiled copper wire under the
Beverage length could likely increase inclination by slowing propogation, in
this case, just as poor earth does.
> > He recommends sloping each end of the antenna to reduce
> > pickup from the vertical drop. Don't you have exactly the same
>
> Think of a K9AY loop, or a Pennant antenna. They act like two close-
> spaced verticals even through they have sloped wires. Both ends of
> the Pennant actually have almost perfectly equal vertical response,
> and look at the great difference in their slope!
Lets not be too hasty to discount the sloped ends effect. A sloper antenna
receives best in the direction of the slope. A vertical drop receives well
from all directions....a perfect "manmade noise" antenna. The fact that a
29 ft Flag has 4.61 dB more gain than a 29 ft Pennant makes sloping Beverage
ends even more compelling.
> > With any antenna of this kind, including the K6STI
> > loop, the flag, ewe, etc., the recommendation is always to use a
> > transformer with separate primary and secondary
Choking the coax at the feedpoint is the effective method at a
balanced-to-unbalanced point, to curtail coax outer shield pickup. See
ON4UN, page 7-19 for choke & independent ground specifications. The 100
ferrite beads may be substituted by coiled coax, or mini coax wrapped around
a choke core.
My recommendation is to Never pass up an opportunity to lower your received
noise level on TopBand.
73 & TY/EA9 DX, om Doug / NX4D
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