Why not model and optimize your own?
"4nec2" is free to download, and has a fairly decent optimizing engine, and
probably has some example models to start with.
"multinec" is also free to download and can do some optimizing. I haven't
used it as much, so I'm not as familiar with it.
As far as gamma matches go, why not use one of the other designs you have
found and change the feed method to a gamma match.
I would also think that the ARRL antenna book might have some example
designs for a 5 el 15m. The latest version includes a copy of the program
YW, and it has a 24 foot boom, 5 el, 15m antenna, and it has a gamma match
calculator.
Looks like about 9dBi gain, 25 dB F/B, and SWR below 2:1 over the band. It
calculates the gamma rod being 0.25 (5mm might work) , 6 inches (15 cm)
away, with 66.9 pF and 18.22 inches (call it 45.5 cm) long.
The program can use metric units, so you could put in metric standard sized
tubing, etc.
----- Original Message -----
From: <df6vp@opretzka.de>
To: <towertalk@contesting.com>
Sent: Tuesday, October 12, 2004 3:36 AM
Subject: [TowerTalk] looking for 15m 5ele yagi design
Hi all!
I am looking for a 15m 5 element yagi design that should meet the
following conditions:
-boom length about 10m
-modern design, means computermodeled & optimized
-elements grounded to boom and not splittet
-matching preferably with gamma match
and at last the criteria nearly no yagi design I found in the internet
fulfilled
-design should be based on tubes using metrical dimension
(I think it´s noch easily possible do build a design based on inch-tubings
with metrical-tubings as the element diameter has an influence on the
length. Am I right or wrong?)
If anybody could provide me such a design and construction details that
would be a great help!
Thanks in advance,
vy 73s,
Joern DF6VP
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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