At 10:43 3/24/98 -0800, you wrote:
>I have just put up a inverted L for 80 M this past weekend. Since i do
>not have very tall trees,poles or room, I have mounted it along side
my
>tower. The spacing is about 3` from tower and the feed point is about
9`
>above ground with 10 elevated radials.The vertical section is 36` and
>the horizontal section is about 30` ,the horz. end is about 30` high.
>Feeding with 50 ohm coax, the lowest swr i can get is 2.4-1 at 3.790
>mhz. Also does not seem to receive very well.All signals are very low
>compared with dipole.
>Do have some interaction from the tower?
>Should i increase the spacing?
==============================>
I have a simlar configuration in my small backyard for 160 meters.
I go up my 65' tower via insulators screwed into aluminum tent poles that
hold the wire about 3 ft from the tower.
Once I reach the tower top, I slope downward towards my front yard and
and tie off to an oak tree.
This gives me a 65' vertical portion and the balance somewhat resembling
a 45 degree downward sloper.
I have no radials but rely on my tower being grounded to my swimming pool
steel re-bar grid as my ground.
To get the SWR down I feed a parallel doorknob capacitor at the feedpoint
and the SWR is flat 1:1.
It works very well, and I would expect yours for 80 to work well, also.
I wish I could run elevated radials.
They will be a plus.
Use ferrite beads as an Rf choke and keep the radials isolated from
ground.
I cover all bands from 160 tru 432 on one tower in a small backyard, with
the inverted L, 1/4 wave sloper for 80, 3 ele on 40' boom for 40, stacked
tribanders for 20,15,10, rotatable dipole for WARC, es beams for
6,2,432 at the very top!
I do most antenna work in the summer as I have to be in the pool water in
order to do some work on the arrays. My yaed is not big enuff for the
aluminum on the ground unless I am in the pool, and the antennas are
supported above same.
73,
Bob Perring
Houston, Texas
Std e-mail: perring@texas.net
Int'l e-mail: N5RP@compuserve.com
<underline><color><param>0000,0000,ffff</param>http://perring.home.texas.net</color></underline>
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