You don't need AutoEZ to see the effect, EZNEC will work. I just ran a model
of a single vertical using 2.00" tubing and one with .090" tubing. The
bandwidth difference was more different than I would have guessed.
John KK9A
-----Original Message-----
From: Jeff [mailto:keepwalking188@ac0c.com]
Sent: Saturday, November 11, 2017 5:50 PM
To: john@kk9a.com; towertalk@contesting.com
Subject: Re: [TowerTalk] 4 square advice
That is exactly the value of something like AutoEZ. You don't have go by
gut feeling making a guess, or based on subjective opinions of others. You
can KNOW the implication before making the physical build decision. While a
model is not a perfect replication of the physical terrain, it's a lot more
reliable than supposition. I'm lazy at the core of my sole so something
like AutoEZ is right up my alley.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message-----
From: john@kk9a.com
Sent: Saturday, November 11, 2017 11:38 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] 4 square advice
I find it hard to believe that using wire vertical instead of a freestanding
aluminum vertical with maybe a 1/2 diameter top section or even a solid 3"
irrigation pipe will make enough bandwidth difference to be concerned about.
John KK9A
To: towertalk@contesting.com
Subject: [TowerTalk] 4 square advice
From: Bill via TowerTalk <towertalk@contesting.com>
Reply-to: cqtestk4xs@aol.com
Date: Fri, 10 Nov 2017 20:51:15 -0500
I'm starting construction of my wire 4 square for 80 meters.
I know the bigger the diameter is (like having Rohn 25 tower for the
radiator)
the better the bandwidth.
I'm using #12 insulated wire, but in an effort to enhance bandwidth I'm
planning using two wires joined at the top and at the feedpoint for each
element. To space them I'm using some old KLM diamond shaped spacers every
five feet or so to keep the two wires approximately 5 or 6 inches from each
other...running the wires parallel to each other.
Any thoughts as to how helpful this will be in increasing bandwidth? I have
about 45 of these spacers and they're just gathering dust, and they are
lightweight, UV resistant and free. Also, any thoughts as to how this might
affect the impedance etc.?
Bill K4XS/KH7XS
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