Paul,
The antenna you are looking at building is a complex antenna consisting of
two parts that contribute to defining how easy/difficult it is to match:
the dipole itself, and the length of the feedline.
In general, a resonant 80m dipole (i.e. 132 to 138 ft.) will have an
incredibly high feedpoint impedance on all even harmonic bands; somewhere in
the range of 2500 Ohms.
By reducing the size down to 120 ft., you will avoid these terribly high
impedances and find it a bit easier to match on all bands. That was a
correct assumption.
Barry's suggestion for an 88' doublet is also a good one.
It requires less space than full size and the reduction of signal strength
on 80m is PEANUTS!
I will also state that your absolute rejection of an OCFD is silly and
unfounded.
Perhaps we should do an off-line chat on this, even on the telephone at my
cost.
I have the time if you like.
No problem if you're not interested. Your loss, not mine.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Paul
DeWitte
Sent: Tuesday, April 14, 2015 6:08 PM
To: tentec@contesting.com
Subject: [TenTec] field day antennas
In my first post I asked if the 80m antenna was 60 ft instead of 66 ft would
it tune easier on 40m.
It should have read 60 ft on a side for an overall length of 120 ft, instead
of an overall length of 132ft.
I do all of my antenna calculations 234/freq which is one side of a dipole
or the right formula for a vertical. Thus the 60 ft on a side.
73,Paul K9OT
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