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Old April 16th 04, 12:22 AM
Incognito
 
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Well the R7 Cushcraft antenna is NOT your Fathers quarter wave vertical --
it is a half wave end fed antenna thus it needs no radials. It is fed at a
high impedance point by virtue of the matching black box at the antenna
feedpoint.

In fact the addition of radials will really screw it up --- read the manual
see URL:
http://www.cushcraft.com/support/pdf/r7.pdf
"THE R7 SHOULD NOT BE CONNECTED TO A GROUND RADIAL SYSTEM".
I ignored this (as an experiment) and found Cushcraft knew what they were
talking about.

The four 49 inch rods at the antenna bottom are counterpoises designed to
isolate the antenna from ground and not long enough to be resonant on any
band.

The bandwidth and efficiency on 40M, I found to be poor. But it works well
enough on the other bands, covering full bandwidth on all bands except 40M
and 20M. You will have to choose the portion of the band you want to operate
on for these two bands.

Tuning the R7 was easy, following the manual instructions.

Be careful of running high power into this antenna for an extended length of
time -- particularly if you horse it beyond resonance with a tuner --
several here have frazzled the traps when doing this.

Using an R7 I was able to work a lot of DX, it does seem to have a low angle
of radiation -- Cushcraft claims 16 degrees.

For more opinions --see url:
http://www.eham.net/reviews/detail/518

This opinion is not to engage in a debate of 1/4 wave vs 1/2 wave verticals
save that for another thread.
--
Incognito By Necessity (:-(

If you can't convince them, confuse them.
- - -Harry S Truman




"JGBOYLES" wrote in message
...
I'm wondering if anybody else made some experiences (good or bad) with
the R7 cushcraft vertical antenna


Hi Lorenz. The R7 will work, needs a ground radial system to work well,

and
will be difficult to get a good match on multibands. Never used one

myself,
just commenting on multiband verticals in general that I have used.
73 Gary N4AST