Hello group, this time I am looking for help about the mounting of my
R7 above of my old Triband yagi, At present I have my R7 mounted on
top of a mast which extends out of the top of my tower by 7 feet, I
would like to know if I were to mount my ATB-34 Cushcraft triband
yagi will I need more than the 7 feet I have available at this time?
I have looked thru the manuals for both antennas and there is no
mention regarding a situation even similar to mine...
So in short what would you folks suggest I use as a spacing between
the R7 and the ATB-34...
Regards,
Marc Tessier - VE3TES
ve3tes@cogeco.ca
-0-
Marc,
I had an R7000 above a T8 log periodic, up in VT.
It was perhaps 1 meter above the beam, on the same mast.
One thing I observed was that the vertical had a slight pattern, on
extended
groundwave tests. 3dB f/b. Turned out that the lpda was excited
by energy
coupled between the feedlines.
It was necessary to use line isolators on the two feedlines, both at
the top and
bottom of the tower, and to move them to opposing legs, to eliminate
the problem.
Later, for lightning protection, I tied the coax shields to the tower
legs, top and
bottom, and repeated the f/b tests. No degradation.
One thing, though... as I recall, the R7 is a bit more sensitive to
its surroundings than
the R7000. Not sure if you'll see a different interaction because
of that.
N2EA
Jim Jarvis, MBA
President - Executive Coach
The Morse Group, LLC
People-Process-Strategy: Achieving Results in a Changing World
www.themorsegroup.biz
coach@themorsegroup.biz
Read our latest newsletter. Go to: http://www.themorsegroup.net/
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