Look at the pattern of your Zepp also.
I use a couple of 80M dipoles plus a 20M dipole (fed w/ladder line)
on the WARC bands to get full coverage with fixed wire antennas.
The 20M dipole gives a figure 8 pattern from 10 to 30 MHz with a
beamwidth varying from 90 to 50 degrees, narrower as frequency
increases and gain increases.
To get an idea of the L pattern, look at the number of half-waves in
each section. Top = approximately 2 wavelengths and vertical is
approximately 3/4 so it should present a low impedance at the
feed point, looking like a 3/4 wave vertical plus a 2 wavelength
longwire (8 lobes, major lobes at 30 degrees to the wire). This
is for 18 MHz. A similar analysis would need to be done for
each band.
In a DX contest once, I was working all kinds of good stuff
on 20M but couldn't understand why there was no difference
as I rotated the beam. It turned out I was on the inverted L !
I had elements for both 160 and 80M tied together at the base
and separated by 10 ft at the 45 ft level. It made a great
all band antenna!
de Tom N4KG
.............................
On Fri, 3 Oct 1997 07:29:07 -0500 "Mike Michon" <michon@eatel.net>
writes:
>
>
>> Has anyone had any experience with the Autek antenna analyzer RF-1.
>> Trying to set up my 160 elevated radial inverted "L"...
>> Is the RF-1 worth the investment ???
>>
>> Thanks......73 Whitey K1VV
>
>Dear Whitey,
>
>I owned one for a short period of time. It was neat to see the
>impedance
>drop as radials were added to my vertical. Unfortunately, I left it
>hooked
>up to the antenna tuner and loaded it up one day. It hated it. I am
>going
>to buy another.
>
>It took a while to get used to the different settings and I had it
>flashing
>through a sequence one time and didn't know exactly what happened.
>(read
>the directions).
>
>I put up an Inv. L about a month ago-- 75 feet vertical and 90 feet
>Horizontal. I am pleased so far. Couldn't work k7k on 18 mhz with my
>CF
>Zepp at 70 feet, but worked them with the L. Sure would like to know
>the
>pattern of the L on 18 mhz, but no antenna modeling program.
>
>Mike Michon
>AB5XP
>Prairieville, LA
>504-622-2608
>michon@eatel.net
>
>
>
>
>
>
> -
> ---
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>
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