Jerry et al:
Such antennas (low to ground, high angle radiators on bands up to around
10 MHz) are more commonly know as NVIS antennas (Near Vertical Incidence
Skywave.) There are quite a few references to such on the web. (See
http://www.co.missoula.mt.us/acs/antennas/NVIS%20EZNEC.htm and
http://www.w0ipl.net/ECom/NVIS/nvis.htm - scroll down to N7NVP and W6QJI in
What Works Well?)
Their use in Ham Radio circles (and military, for that matter), is for
improved <skip-zone> coverage, i.e., that area around a transmitter where
ground wave fades out and before the first E- or F-layer bounce on the ground
occurs. Most literature that I've read on the subject considers this distance
from 50 to 500 or so miles out.
Hams would use such antennas for domestic contesting, i.e., SS or Field
Day, or for EmComm activities where local infrastructure has been damaged and
receive points are beyond V/UHF range from the disaster sites.
73 de
Gene Smar AD3F
>
> It is possible to build arrays that squirt the signal straight up with
> significant gain, but the beamwidth is fairly narrow, and these antennas
> don't seem to have any applications in ham radio.
>
> Jerry, K4SAV
>
> Joe Barnes wrote:
>
> >I am considering putting up a wire about 1/4 wave below my 75 meter
> >inverted vee that is 10 percent longer than the inverted vee to use it
> >as a reflector for closer in ( within 700 miles or so) communications.
> >Does anyone have any experience with such a thing? The inverted vee is
> >at 95 feet at its apex. Thank you, joe barnes N4JBK
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