[Top] [All Lists]

Re: [TowerTalk] Suspending a OCF Windom from a tower

To: <>
Subject: Re: [TowerTalk] Suspending a OCF Windom from a tower
From: "Kenneth Goodwin" <>
Date: Wed, 18 Jan 2012 09:46:17 -0600
List-post: <">>
The compromise in an OCF dipole is a higher SWL across all of the dipole's
amateur bands for multiple band coverage; in other words, it is a
compromised design that affords multiple band operation for the disadvantage
of a higher SWR.  My experience is that an SWR of less than 3:1 is likely to
be seen in an OCF dipole especially over the 'harmonic' frequencies.  This
is to be expected and not a downside.  You'll see some OCF providers state
that an antenna tuner is desired for optimum operation.  If the OCF antenna
is installed in an inverted vee as in your case, the input impedance will be
less than if it were installed in a completely horizontal orientation.  But
if your SWR is less than 3:1, I would not worry about it.  I have found that
any attempt to optimize the leg lengths only results in higher SWRs on some
frequencies with lower SWRs on others.  Again it is all a compromise with a
zero sum gain.  Having the center part of the antenna near/on the tower
would not be optimum.  But in the real world, physical constraints trump
electrical objectives.  A inverted vee fan dipole might allow optimization
on the desired operational frequencies but if your OCF works and can be
safely loaded, be happy.  (I got a good laugh from the amateur that had his
at 120 feet - a piece of spaghetti would work at that altitude!!)  Ken K5RG


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>