I'll second Mark's approach. I used this technique on a flat-top dipole
for 80/75 and it increased the bandwidth significantly. Not enough to cover
3.5 to 3.8 but this antenna was quite low, abt 30' max.
I currently have a 40M 'Fan' inverted vee with the apex at 50' and it's
under 1.5:1 across all of 40M.
In both antennas I observed another effect... adding the second wire
significantly shortened the entire antenna. As I recall (6 or 7 years ago),
the original 80M dipole ended up 10' or so shorter after adding the second
conductor.
Spacing of the second conductor at the far end on the 80/75 was 8' - only
because I used some 1X2s that were 'in stock' as spacers. The 40M fan I
currently have is spaced abt 3' - again arbitrary.
Enjoy! 73, Bill N2BC
-----Original Message-----
From: Lowell, Mark <mlowell@noclant.navy.mil>
To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Wednesday, October 21, 1998 9:22 AM
Subject: Re: [TowerTalk] Best wire type antenna for 75m/80m DX coverage
>
>I don't think anyone has yet offered the following, simpler solution to
>your quest:
>
> Try making yourself a fan dipole. Connect two dipoles to the same
>feedline, cut one for the higher, and one for the lower frequency of
>interest. Some achieve this by using 450 ohm ladderline for the legs,
>providing 2 conductors, but there will be less interaction if separate
>wires are used and the dipole legs diverge from each other a bit. This also
>tends to simulate a bow-tie configuration, adding to the bandwidth.
> This should meet your needs without requiring a trip outdoors to change
>anything.
> As an alternative, feeding this arrangement with ladderline, as someone
>already mentioned, can give you good multiband operation, as long as your
>tuner has an internal balun.
>
> --...MARK_N1LO...--
>
>--
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>
>
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