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If
you are or were in the same boat as this writer, the above selection was
through necessity. One might ask, “What could be the necessity”? Why
would a fairly knowledgeable Amateur/Radio Operator, exchange some
well-performing wire dipole antennas/beams for a vertical system? Let’s
go for a “plain and simple” reason. I’ll try and keep the
explanation short and sweet.
We had an opportunity to purchase
property in a ‘55’ or older adult retirement complex here in Yuma,
AZ, at a very good price. We had
planned on retirement to the desert country and this seemed to be tailor made
for our needs. Purchase was made from a very good friend’s advice and
in fact he had bought two parcels, and we had very colorful brochures to go
along with everything else. Unbeknown to me was the very strong language in
the “CC&R’s” that prohibited
antennas, towers, dipoles, guy wires, etc. One of the people sitting on the
Board of Directors was a Ham. But, he was also a retired dentist and most of
his radio activity was with VHF/UHF. Another reason is the size of the lots.
Most run 40 feet by 60 feet. Hardly enough to do anything with, without
cluttering it up and producing some sort of spectacle. More on that later.
The one thing the CC&R’s did allow
(through necessity) was the mounting of a vertical antenna on the RV, travel
trailer, etc., on the lot. As long as it was connected to the unit, was all
that was required. This left a small door open, for those that do read the
small print. More on this later.
Getting into the nuts and bolts of this
article, let’s start with identifying it as the “Butternut
HF6V”, improved to the HF9V, with the 160 Meter coil. I do use this
system from six through 160 meters.
(more to follow in Part
2)
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(Part 2)
As
we move along with ideas and experimenting that has worked for me, I will not
try and address coil inductance, capacitive reactance, etc. I’ll try
and stick with those items that are easily identified and understood. As I
said before, keep it “plain and simple”.
I guess the main item in the
system for keeping it this way are the “open wire coils”. These
have proven very broad banded, at least in my application. The model I have
is one of the early units, developed in the early ‘80’s. I
believe that Bencher has made several changes and there could be some
innovations out there, that I’m not familiar with. To see if we are on
the same page, my unit is fed at the bottom where the 160 Meter coil is
mounted. Fed in parallel with two door knob capacitors at 200PF. To go one
step further, this feed line is a length of RG11, 11’/6” long. It
is used as an impedance matching unit. Others have used one or two other
types of matching and have run into trouble. It seems that many of these
antennas go on the used market without the RG11. I have given out the above
measurement to several who have asked for it. Does not seem to make much
difference how much <50> ohm coax is attached to the RG11.
For
those that may have that important question lurking somewhere, “how
about ground radials”? Yes, I have as many as I could string out on
this lot of 42’X60’, and it is a corner lot. My system was
originally installed in 1994, as we purchased it in 1989, and we were both
still working, there wasn’t very much here. Lots of dirt,
sand and gravel. I went out a purchased a small hand pick and Digger, being
sold as the “Lost Dutchman Gold Mine Special”.
(More to follow in Part 3)
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(Part 3)
Didn’t find his old mine, but I
buried four 63’ wires, several cut for 40 meters, threw in some extras for
posterity, and very happy I did. I also have two 12’ ground rods at the base of
the antenna. I am a firm believer in radials. At our previous location in Reno, I was fortunate to
have enough property for a very good antenna farm and one of my antennas was
the Hy-Gain HT18 (my 2nd one) with an excellent radial system
underneath and around it. At least we made the ARRL Honor Roll, 5BDXCC, 5BWAZ,
along with other accomplishments.
Getting
back to the coils, I use clip leads, No 12 stranded, covered wire, with
alligator clips on each end, to provide me with a means of going just about
anywhere I wish to travel on the bands. These days, just about all my operating
is done on the Air Force Mars frequencies. As you all know, they are really
spread out. Incidentally, I’m able to cover the Army and Navy frequencies as
well. At least those that I have explored. The butternut coils are very broad
banded and lend themselves very nicely to this kind of configuration. For the
one or two changes I used to make, I’d just bounce out the back door of the ham
shack and move a couple of clips and there we were. Since my wheels went bad,
no more bouncing. The XYL has been performing that part of the operation and
doing a great job, probably going to have to give her a raise. MFJ has a device
similar to what I used on my 80M slopers some years ago-- could make the tap
changes automatically with a flip of a switch, with a couple of small 12VDC
relays.
I am not sure all HF6V’s or
whatever model, are the same, I have found that my system is very broad banded
on 20 and 40 meters. I am always surprised how far I can go on these two band
areas and not use the internal tuner in either of my station rigs. In case you
are wondering, I use an Icom 746 PRO, with the Ameritron AL-811H behind it. The
other station is also an Icom 756 PROII, with an Alpha 374-A behind it. I do
not need to use either built in tuner, to go where I wish to go with the
antenna set up, as I have described the adjustments previously. I usually run
between 500 and 600 watts to the antenna. After all, when you address our
CC&R’s and the close proximity of my neighbors – let’s not go asking for
trouble.
Presently
while changing over to “RP” for our winter time Region 6 frequency of
operation, it is a challenge for many stations to reach down and be able to
cover the frequency, without investing in additional real estate or trying to
move into the neighbors property and his or her friendliness. Would be nice to
be able to extend an existing good working 80 meter dipole, for the extra
coverage needed. Not in the cards for most, so as hams have been doing since
radio communications have begun, time to improvise and/or substitute. Even with
the HF6V/HF9V, radical changes are available. An old age visitor
by the name of Mr. Arthitus has moved in and made so many of
the things (soldering, building, drilling, etc,) so difficult, it is sometimes
hard to realize just how easy it was to
do all the technical things, that we cut our teeth on, in the field of
technical applications.
(More to following Part 4)
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