Gary: Good questions. I use Opti-Beam antennas, but not those you have
chosen. You will find them easy to construct....they are the best made
you can buy as far as I am concerned. Booms are well marked etc as are
all elements. Read the assembly insturctions through at least two times
while viewing the parts so you are familiar with them. The boom to
element plates are unique, and will confuse you a bit until you
understand the assembly process. Nothing to it, just take your time
getting all of the elements parallel to the boom. Use of a 4 foot level
will help a bunch.
The rule of thumb is to have no less than 1/3 of the mast in the
tower...and it is a good rule. Write an e-mail to Tom at OptiBeam (the
owner) and ask him about separation. Tom knows his antennas and can
advise better than anyone else how much separation is necessary. As a
guess I would think with those two beams that ten feet of separation
will be more than adequate. You can find his e-mail address on the web
site. Toms english is very good....and he will answer you.
Your question about 80 feet in height is a bit more complex. Answer
depends on what you are planning on doing with the beam.
If your objective is to be the loudest on the band during contests then
the answer is it will either be too high, too low or just right
depending on the conditions at the moment. From the east coast an 80
foot tri bander is too high during the day to EU/AF/SA, but during band
openings and closings it will work just fine. A second antenna at about
40 feet will outperform the 80 footer during those times. To the
pacific 80 feet is never too low, but often not high enough. If you
are first a dx chaser, then I suspect you will be quite happy with it at
80 feet. Just remember there will be times when others will beat you
out because their beams are higher or lower or both. That is the beauty
of stacking, so you can cover all of the angles.
I have an OptiBeam OB16-3 at 80 feet and a Force 12 C3E at forty feet.
It is amazing how often the little 2 element C3E will be MUCH louder
into EU than is the big one. On the other hand, there are times when I
am told "you are the only W I hear", or "You are the loudest W on the
band". this never happens with the C3! Living close to the coast helps
here too, it is not all the antenna. My plans are to stack a pair of
OB16-3's at 40 and 80 feet and lock them together rotationally. This is
the "absolute ideal" for eu/sa/af from here, as all of the angles get
covered. I will still be weak to the pacific however because to get a
much better signal out there I need much more height...to at least 120
feet....and I cannot get there just now. I am usually able to work dx
easily into the pacific, but contesting is another matter.
Keep that A4S where it is if you can, or put it on a tic ring rotator.
Often your new antenna will be MUCH better than it, but not always. 80
feet on 40 will open a new world for you, but don't expect miracles. It
would work significantly better at 100 or 120 feet but only you can
decide if it is worth that extra hassle. Of course at 120 feet the 40
ain't gonna do a very good job domestically. Everything has its trade
offs. That is why stacking is so popular among contest stations. They
need to cover all the angles. Good luck and have fun. 73 bob de w9ge
>
>
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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