Actually NOT.
If you model it you will see that the pattern 3 db points on elevation
are 15 degrees through 75 degrees with a very broad maximum around 40
degrees. Straight up is a minimum on the pattern.
This is a GENERAL PURPOSE height that scales well to other bands. It
will behave the same as a 75 meter dipole at 93 feet or a 40 meter
dipole at 50 feet.
Also kindly remember that the point of the post was comparing this
antenna with a C31XR on 18.1, a frequency not in the C31XR design. I
was not trying to specify the killer antenna for 17 meters, just
emphasize the degraded idea of using the C31XR for that band.
A 20 foot high backyard dipole for 18.1 MHz WILL beat trying to use a
C31XR, particularly at the end of nearly 700 feet of coax as described
by the original poster.
Dipoles get a lot of bad press. They really are a solid simple
antenna. When the scores are added up at end of the contest, a lid
with a beam will be thrashed every time by a good op with a dipole.
Biggest db's of all are between the ears.
----- Original Message -----
From: <n4kg@juno.com>
To: <TOWERTALK@contesting.com>; <k2av@contesting.com>;
<wa9als@starband.net>
Sent: Sunday, June 23, 2002 7:29 PM
Subject: Re: [Towertalk] Re: [Force 12 Talk] XR dilemma
> On Sat, 22 Jun 2002 "Guy Olinger, K2AV" <k2av@contesting.com>
writes:
> >
> > You would do considerably better on 18 MHz to just cut an 18 MHz
> > dipole and string it 20 feet up in the air. Signals are quite
strong
> > on 17 meters.
> >
>
> At 20 ft, MOST of the radiated energy will pass into outer space.
>
> As most readers of TowerTalk know, I strongly recommend 40 ft
> as the minimum height for effective coverage of the upper angles
> supported by the ionosphere on the High Bands (20 through 10 M).
>
> Tom N4KG
>
>
>
> ________________________________________________________________
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