Hi Dave,
I was looking over my logs from back in Florida the other night. I had
forgotten just how much DX I was able to work with 100 watts and
a 50' high "T" antenna fed against ground on 1/2 acre lot. The big
thing was adding the radials (about 2000') of wire under the antenna.
Before adding the radials, the antenna was an air cooled dummy load.
Although it still had room for improvement, the 25 or so somewhat
asymetrically placed radials had a profound effect on my ability to
be heard (especially in Europe). As far as receiving goes, I used
a JPS ANC-4 to help provide some rejection of local noise. I still had
a long way to go, but it was a big help.
When I was living in Ohio, I had a similar situation - 55' tower top loaded
with a Cushcraft A3 and inverted V's for 40 and 80. The tower was
shunt fed on 160 and seemed to work "okay" but my radial system
was not as good as in Florida (about 15 1/8 wave radials vs 25 1/4 wave).
The interesting thing about this installation was on receive. When I switched
from the shunt fed tower to my 40 meter inverted V thru a B&W shorting coax
switch, the shorted stub on the shunt feed detuned the tower, and made
the 40 meter inverted vee a very quiet receive antenna. I still recall hearing
UG6GAW CQing plain as day one evening on the inverted V. When I
switched to shunt fed tower, he was unreadable. Who knows - with an
amp and a few more radials, I probably could have worked him :) :)
If I had a small lot to work with, I would go with a single tower tribander/
2el 40, 1/4 sloper on 80 and shunt feed on 160. I think an array of short
verticals can be made to work on receive if careful attention is paid to
detuning nearby resonant structures, but I haven't actually had time to
try it (I am anxious to build one at my QTH in LA).
73 de Mike, W4EF...............
----- Original Message -----
From: "David L. Thompson" <thompson@mindspring.com>
To: <towertalk@contesting.com>
Sent: Friday, August 31, 2001 4:03 PM
Subject: [TowerTalk] What about hams with small lots???
>
> I keep seeing 4 squares on 80 and 165 foot towers with stacked 3 el 40 meter
> beams. Well I suspect that most don't have
> the real estate to use anything like this. What about effective antennas
> for those of us on small lots (for those fortunate enough
> not to have antenna restrictions).
>
> I have tried over the years to put up good antennas on my 1/2 acre tree
> filled lot with a two story house in the middle. I think a large chunk of
> hams on the reflector would like how to put together effective, competitive
> stations that overcome the problems of interactions and RFI that I have run
> into...Especially for those of us who are trying to work 160 to 10 or even
> VHF. I think 20 to VHF can be accomplished easy enough, but beyond a 2 el
> 40 how do we get antennas to put out a large signal on 40, 80 or 160 and not
> be an alligator (no RX antenna).
> Then there is the problem of interaction with antennas all over the place.
> I have my ideas ...how about yours?
>
> Just my two cents...
>
> 73 Dave K4JRB
>
>
>
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>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
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