Don, there is height of 31.5ft but electrically radiator is longer than
that, even longer than it should be so the series capacitor is in line with
radiator. So there is no way you can make assumption that there is 12 Ohms
impedance at the feed point on 80m.
73 Danny N4EXA aka E73M
---------------------------------
Danny Horvat, E73M
Antennas & Accessories
www.MyAntennas.com
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
Donald Chester
Sent: Friday, October 23, 2015 1:14 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Laws of Physics Repealed!
First there was the Gotham Vertical.? Then the infamous Max-Com automatic
antenna matcher.? Now, Cushrcaft is in on the action.
"R9"
vertical.? Low angle radiation gives incredible, easy, world-wide low band
DX on 75/80m and 40m, plus it covers 30 through 6m with low VSWR on all
bands, with broadband matching transformer; no antenna tuner needed. Low
profile blends inconspicuously to keep your HOA happy.? 31.5 ft tall.? Best
of all, NO RADIALS NEEDED!!!
Only $639. Just plug in your plastic radio and talk, talk, talk!
See November, 2015 QST, page 2.
Amazing
that hams (or maybe I should say HAMs) swallow that crapola.? 31.5 ft is
only an eighth wavelength on 75/80m. The base impedance of a 1/8 wavelength
vertical is about 12 ohms. No matter how much gimmickry such as stubs,
loading coils, toroidal transformers and porcupine spikes are added, that
thing will basically be a dummy load unless it is used with a SUBSTANTAL
radial ground system.? A couple of 8' ground rods won't cut it.
I had always considered Cushcraft, which has been in the business for
decades, a reputable outfit, but this makes me wonder.
Don k4kyv
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