Ian;
I successfully phased four (4) of the MFJ-1792 verticals as an 80 meter
4-Square with 40-50 radials each 60'-70' long. There is no adjustment on
40, it is a 1/4 wave on 7 MHz. I trimmed a few inches from each spoke
until it was resonant at 3.775. Then removed the same amount from the
other three verticals spokes, and connected all to a Comtek Hybrid
Phasing Coupler.
For the $$, I thought they were well built, and the Teflon loading coil
for Top-Loading was an efficient method of loading a short antenna.
I suggest your friend remove the 15 foot wire to see what affect it has
on SWR.
The aluminum spokes are trimmed to raise 75m-80m frequency.
Good Luck!
On Fri, 19 Nov 1999 20:09:04 -0000 "Gian Luca Cazzola" <glcazzola@iol.it>
writes:
>
> Dear friends,
> a friend of mine, Mauro I4JEE has bought an MFJ 1792 80-40m vertical
> antenna.
> He has assembled it on a garage roof-at the side, about 12 feet from
> the
> ground. He has connected 5 radial wire, about 35
> feet long. He has also connected a ground wire (abt 15 feet long).
> The antenna has lower swr at 7.5Mhz (more than swr 2,5) and at
> 3,6mhz (about
> swr 4). Tomorrow he will try to connet other
> 4 radials, but I think he will solve nothing.
> Does anybody know or own this (bad and strange behaviour) thing
> called MFJ
> 1792?
> Can he suggest something to solve the problems?
> Thanks es 73
> Ian IK4EWX
>
>
>
> --
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>
73,
Jim Miller, K4SQR
A 4-Square Station
--
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