You might check the Hints and Kinks in the June 77 QST. Wes Hayward, W7ZOI,
decribes a dual band feeding system that allows a quarter wave vertical on
40 M to be also fed on 20 M as a half wave vertical using the same feedline.
I think you could use the same scheme with your 80 M vertical. The antenna
is fed with a series LC resonant on 40 M and a shunt C. On 40 M the series
LC is essentially a short circuit and the shunt C is not significant. On 20
M the series LC looks like an indutance and with the shunt C it forms an L
network. The values are fairly critical, but Wes gives suggestions in the
article.
Recall that verticals work best with good grounds. Put lots of wire in the
ground.- Dr. Megacycle KK6MC/5
--
James R. Duffey KK6MC/5
30 Casa Loma Road
Cedar Crest, NM 87008
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