Thanks -- should have thought to look there.
>From those charts, best-case gain is achieved with a .35-.4 WL boom; the
penalty at .2 WL is ~1.5 db and at .5 WL is less than .5 db. Best case F/B
requires a .3 WL boom, with a 8 db penalty at .2 WL but a serious 25 db
penalty at .5 WL (the best case F/B at .5 WL is shown as slightly below 15
db).
Are there parasite tuning combinations other than those in Lawson's table
2.3 that would produce a better F/B at .5 WL?
73,
Dave, AA6YQ
-----Original Message-----
From: owner-towertalk@contesting.com
[mailto:owner-towertalk@contesting.com]On Behalf Of n4kg@juno.com
Sent: Wednesday, January 30, 2002 21:24 PM
To: TOWERTALK@contesting.com; dhb@mediaone.net
Subject: Re: [TowerTalk] re:Non-traditional antenna designs
On Wed, 30 Jan 2002 "Dave, AA6YQ" <dhb@mediaone.net> writes:
>
> Given that one can vary element lengths but not element spacings,
> how close to monoband performance can one get with this approach?
>
> 73,
>
> Dave, AA6YQ
A 14 to 18 ft boom is a reasonable compromise from 10 thru 20M.
Band 14 ft boom 18 ft boom
20M 0.2 WL 0.26 WL
15M 0.3 WL 0.38 WL
10M 0.4 WL 0.52 WL
See the W2PV Yagi Antenna Book Chapter 2 Figure 2.9
for plots of typical 3L Yagi designs on boom lengths from
0.1 to 0.7 WL
Tom N4KG
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