Date: Tue, 27 Aug 2013 18:18:57 -0700
From: Robert E G Earl <bearll@telus.net>
To: towertalk@contesting.com
Subject: [TowerTalk] rotating delta loop
Message-ID: <521D5001.5080008@telus.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I have made a 4 element deltaloop on a 30 foot boom for 20/17/15/12/10
meters in 1983. I have since refurbished the antenna and I am now
re-installing at my new address. The gain for 4 elements is around 11.5
dbd. If anyone is interested, I have put together a website that
describes my findings. I can work most on the 1st or 2nd call. The
antenna is very quiet for those very weak ones. My website is
WWW.deltaloopantenna.ca or com.
73 Bob VE7SQ
### here it states a 4 el 20m monoband delta loop....on a 24.6 ft long boom.
http://www.deltaloopantenna.com/wp-content/uploads/2010/07/20m-4-ele-delta-loop.jpg
## Then here it depicts 14.46 DBI gain
http://www.deltaloopantenna.com/wp-content/uploads/2010/07/20m-4ele-deltaloop-az.jpg
## Then here it depicts a 9 deg take off angle for the main lobe.
http://www.deltaloopantenna.com/wp-content/uploads/2010/07/20m-4ele-deltaloop-elv.jpg
It would have to be up 100 ft to get 9 degs. ... = 1.5 wavelengths.
## side lobes are only down 18.34 db. 2:1 swr points are only 200 khz
apart. It needs more tweaking.
## To get real gain vs a dipole..and both at the same height, subtract 2.2
db. Then subtract another 6 db for the ground gain.
14.46 – 8.2 = 6.26dbd. A plane jane dipole is already
8.2 dbi .
## so its 6.26 dbd on a 24.6 ft long boom. That’s pretty good,
considering F12 rates their 4 el yagi on a 30 ft boom at 6.0 dbd.
A 204BA is aprx 5.5 dbd. My 5 el F12 yag on a 36 ft boom is only 7.3 dbd.
A 3 el on a 18 ft boom is only 5.2 dbd. The F12 6 el
on a 44 ft boom is 7.8 dbd.
## How long is each of the three spreaders ? Im guessing at least 13-14 ft.
That’s 39-42 ft in total.
## What this needs is a 40 ft boom....and 2 more eles. Then it becomes a
flame thrower. Keep up the good work.
later........ Jim VE7RF
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