Thanks for this article, Ron.
As many people on this list know, I have used a G5RV antenna on several
occasions, including for a year or two with the drivable RV that my XYL and
I had from 2007 through 2014.
Although the antenna did work for me on 20 meters, and even on 40, I found
its performance not to be very good at all on 10, 15, and, of course, 80
meters.
This led me to switch to the Alpha Delta DXCC antenna for my RV setup.
Last year at our older camp site, the DXCC worked extremely well on 10
through 40 meters, and I even got it to tune up on 80 and 160 meters.
It does show what a well-manufactured truly multi-band dipole can do, even
though it is still a compromise antenna.
As many of you also know, I'm trying to get my DXCC to work well this year
out at the RV camp site, but have not been as successful, probably due to my
antenna configuration, and to the fact that a good portion of the antenna
is over the RV, which has a metal roof.
Anyway, although I don't want to bash the G5RV too much, because I do know
it has its utility for some people, it's good to know what those who have
thoroughly tested the antenna have to say.
Tom Behler: KB8TYJ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Dr. Ronald E. Milliman
Sent: Monday, July 13, 2015 11:47 AM
To: [log in to unmask]
Subject: Truths about the G5RV antenna
There is considerable debate about the G5RV antenna, e.g. how well it works;
is it truly an all-band antenna, etc. In fact, we have had similar exchanges
right here on our Blind Hams's email list. In my pursuit of the best
antennas to erect in various situations, including the current location of
my new home in a highly restricted area, I have studied the G5RV and in the
process of my research, I found the following information written by my good
friend Buck over at Buxcomm. If you don't know Buck, he is an old ex-marine.
He's pretty rough around the edges, as the expression goes, but old Buck
tells it the way it is with no BS. Here is what Buck says about the G5RV
antenna, which is pretty much the same thing that all other really
knowledgeable people say about the G5RV:
*****
".About thirty years ago we ran several antenna range tests on the G5RV. We
used a high-frequency,
National Bureau of Standards (NBS) calibrated Potomac Instruments FIM-41,
field-intensity meter. The
companion antenna was the HF NBS calibrated measurements dipole.
The weather was clear, and the transmitting station was adjusted to 100
watts, into an original G5RV
antenna.
The purpose for conducting these tests was because we had constructed
several G5RV antennas and the
performance of each one was, at best, poor! Our findings were despicable on
the HF bands, with the
exception of 20 meters.
Sometime later we came across some of Mr Varney (G5RV) notes. In his notes
and description of his
G5RV antenna, we learned that he had really designed the G5RV to be used as
a good 20 meter antenna,
nothing more. Somehow over the years his antenna became (assumed to be), an
HF or multiband
antenna. This assumption was so far from the truth and from Mr Varney's
original design.
THE G5RV IS NOT A MULTI-BAND ANTENNA ! The only HAM band where it has a zero
(0)
current node IS at 14 MHz (20 meters).
For several years, we've attempted to give notice to our friends and
customers that relate to the G5RV.
Most of our findings have fallen on deaf ears, or to the G5RV users who
would not hear the truth.
Any antenna, (non-resonant long-wire, included), can be tuned to resonance
on almost any HAM band.
This is why many good manufacturers build and sell antenna tuners. You can
confirm this notion each
time you use an HF mobile antenna.
HERE NOW, IN HIS OWN WORDS:
312
After several years, our findings are being realized by some of the leading
transceiver
manufacturers. To support our findings, on page 8 of several YAESU
transceiver
manuals, Yaesu engineers inserted a short paragraph that finally put-to-rest
these
findings. The following text is an excerpt from one of those Yaesu
transceiver manuals
"ANTENNA CONSIDERATIONS
Every effort should be made to ensure that the impedance of the antenna
system be as close
as possible to the specified 50-Ohm value. Note that the "G5RV" type antenna
does NOT
provide a 50-Ohm impedance on all HF Amateur bands.
Any antenna to be used with the FT-950 must be fed from the transceiver with
50 Ohm coaxial cable. Therefore, when using a "balanced" antenna such as a
dipole, remember
that a balun or other matching/balancing device must be used to ensure
proper antenna
performance. etc... "
Excerpt from Page 8 FT-950 OPERATING MANUAL.
We like to sell antennas, and we like to sell the G5RV (+), however, it is
our sincere objective to be
completely above-board about this antenna. It is NOT an all-band HF
antenna."
*****
Dr. Ronald E. Milliman
Retired Professor of Marketing
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