HI Greg
You need to detune the tower and the 4 square will work fine. But if you want
to have a good RX you need a Horizontal Waller Flag at 140ft or more.
You can see the two webinars about Waller Flag at www.wwrof.org archives
http://wwrof.org/webinar-archive/n4is-waller-flag-construction/
http://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-lot/
Doug NX4D 160m DXCC is # 304 confirmed, from a 1/5 acre lot, I started 3 years
later with a Waller Flag and am at #293 confirmed. I sure mist a 4 square for
TX ,. because since 2006 I've heard 316 countries on 160m from my acre city lot
in Fort Lauderdale on the last 10 years.
Noise is very high here on the city
The best way you can destroy the station for RX on low bands is to use elevated
radials and NOT DETUNE IT during RX.
The concept is simple! All your wires makes only one receiving system. It is
necessity to keep all of them clean.
Performance is subjective, if you have nothing to compare you never know what
you are missing.
If you listen only vertical you are missing 50% of the band.
Regards
JC
N4IS
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of GaryK9GS
Sent: Sunday, August 27, 2017 5:51 PM
To: Greg <n4cc@windstream.net>; 'topband' <topband@contesting.com>
Subject: Re: Topband: 160 4 square
Take a look at the K3LR website. This is essentially what Tim does, only
instead of a 4-square, his array is a 5 element parasitic array with three
active elements. K3LR just gave a presentation on his station this weekend for
the Society of Midwest Contesters and this was mentioned.
73,
Gary K9GS
-------- Original message --------From: Greg <n4cc@windstream.net> Date:
8/27/17 1:56 PM (GMT-06:00) To: 'topband' <topband@contesting.com> Subject:
Topband: 160 4 square Question for the group...
>From a 140 foot freestanding tower, I will suspend 4 pieces of phillystran
90 degrees apart from the top of the tower. Antenna wire will be attached to
the phillystran such that verticals will be dropped to create a 4 square.
I will have as much vertical length as practical and still obtain the 4 square
spacing required -- but the vertical length certainly will not be close to a
quarter wave. The intent is to use the verticals as a 4 square.
In thinking of ways to increase the electrical length, should I run wire back
toward the tower from the top of the vertical section to get the full
1/4 or use a T with wire going back toward the tower and down the phillystran
to create a "top hat" effect -- or does it matter? Obviously this is a
compromise but hopefully still an effective antenna with directional gain.
Thanks in advance for your thoughts. 73, Greg-N4CC _________________ Topband
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