[TowerTalk] 10m OWA 24'

[john at kk9a.com]

Six elements on a 24 ft boom for 10m seems excessive - even for an OWA.



To: "Joern DK5TT" <dk5tt at opretzka.de>, <towertalk at contesting.com>
Subject: Re: [TowerTalk] 10m OWA 24'
From: "Bob" <rabisch at hotmail.com>
Date: Mon, 2 Nov 2009 16:54:05 -0500
List-post: <towertalk at contesting.com">mailto:towertalk at contesting.com>

If you change the taper or size of the elements it will change the
performance.

Another possibility would be to start with a Hygain 105CA which is on
a 24' boom.  By adding one element you can make it into a 6 element
10 Meter OWA on a 24" boom.  Using YW (yagi for windows optimizer
program) you can obtain:

(these numbers assume the antenna is mounted at 32 feet)

Freq (MHz)  28.0   to  29.0
Gain (dBi)  15.54  to  15.84
I/I  (dB)   22.4   to  23.03
SWR         1.11   to  1.05

Element Taper (in): 1.045    .875    .625    .438
Element Spacing (in):  0    49    68   133   194   283

I can't recall the dimensions or the reference but someone also came up with
a dummy element made out of PVC to rebalance the beam.

Nice way to eliminate the hairpin and have a flat SWR across 1MHz of the 10M
band.

It all depends on what you have available to work with.

Bob
K4QHH