Bill:
I assume that your primary interest is DX from your post. Since towers or
out of the question, it would seem that you are limited to verticals. You
can improve the efficiency of a single vertical with a ground screen. You
can improve the directivity and gain by going to a vertical array. I live in
a restricted antenna neighborhood and have had good results using a
screwdriver vertical mounted in the center of a 16 by 20 foot rectangular
ground screen made from aluminum screen door material. The ground screen was
covered with barkdust so as to not be visible. I have enhanced the
performance on 15 meters by adding a parasitic director and reflector. The
array was optimized using AO for maximum front to back ratio to minimize TVI
that my neighbor was complaining about. With my neighbor to the rear, the
array is pointed towards Europe and Africa. The measured F/B ratio on 15
meters ( the only band that causes TVI )is appoximately 40 dB. The
screwdriver and parasitic elements are short enough as to barely be
noticeable above the fence top from the street. I get signal reports on 15
meters comparable to others in the area with towers from Europe and Africa.
I have gotten several skeptical responses when I describe the antenna that I
am using. The antenna is also quite respectable on the other HF bands except
80 meters where the efficiency is less than 10%. The pattern is essentially
omni directional except on 15 meters.
Best Regards,
Thor K5AGE
-----Original Message-----
From: towertalk-admin@contesting.com
[mailto:towertalk-admin@contesting.com]On Behalf Of Bill Axelrod
Sent: Sunday, March 31, 2002 6:37 PM
To: Towertalk@contesting.com
Subject: [Towertalk] Antenna choices in a restricted neighborhood
I'm looking to tap the collective wisdom of this group. I live in an
antenna restricted neighborhood. (Please no flames - there are real reasons
why some of us live like this) While transmitting antennas are not allowed,
I have been able to put up two - a Gap Titan and a G5RV as an inverted Vee
with the apex at 36 ft. My back yard is rectangular, about 95 feet by 40
feet. The vertical has been up for about 7 years so I figure I'm pretty
safe from the Antenna Police.
While I've done marginally well with this setup (~285 countries and DXCC on
all bands 80 through 10), I know my set up is far from optimum. I want to
do better. Short of putting up a tower and beam which surely would attract
the Antenna Police, I'm looking for ideas on what I could do to get the best
antennas I can in my available space and within the restrictions given.
That limits me to two ~36 ft support poles and two PCV pipes at 10 ft
holding the ends of the Vee (similar in visibility to what I have now).
I'd like to avoid (or minimize) the use of a tuner to aloow quick QSYs.
Now, I use the Gap from 40 to 10 and keep the Vee tuned to 80 meters. Cost
is not the limiting factor.
I would appreciate any ideas the group may have.
Thanks and 73... Bill K3WA bill@axelrods.org
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