> Date: Tue, 28 Apr 1998 07:43:33 -0700 (PDT)
> Oh, now this is interesting - so maybe a poor man's rhombic could be made
> from one good-sized support?
That's the idea. I had two at WXEZ FM on 160 meters, with a 350 ft
> Run a slantend wire up from ground level,
> back to ground level, terminate at one end and feed at the other. Hmmm...
> It might have to be a pretty high support, but Western Wash has some
> pretty sizable Douglas Firs.
These antennas are not the same as the "toys" sold by B&W and others.
Long wire arrays require actual design work to align the lobes. The
antenna must have:
1.) proper height to align the main lobes in phase from
2.) legs more than 1 wl long at the lowest frequency.
The real Inverted V is nothing more than a Rhombic, turned on its
side. The earth below and around the antenna forms the missing
half, at the expense of some additional loss.
> Anybody tried this configuration below 20-meters?
Yep, on 160 and 80. I ran coaxial lines to the far ends, and used a
phase adjustable combiner to sum the termination end back into the
feedpoint. This is worth about 2 dB more gain, because the power
normally dissipated in the termination resistor is added back in at
the transmitter and contributes to ERP in the desired direction.
Two antennas cover four directions, and work over at least a 2:1
frequency range with fair to good gain and excellent F/B.
Sorry John, the Inverted V is correctly described (at least
according to textbooks by popular professionals like Kraus, Jasik,
Balmain, Kuecken, and others) as a half-Rhombic turned vertically.
The popular Ham Inverted V is really just a droopy dipole that
incorrectly is called the same name a vertically polarized
half-Rhombic has used for many years in commercial circles.
I see nothing wrong with calling it an inverted V dipole, but it sure
isn't an Inverted V antenna, and it sure isn't that goofy thing Denny
Had sold to B&W in the early 80's.
73, Tom W8JI
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