At 05:51 PM 10/28/97 -0200, you wrote:
>Hello guys,
>
>I would like to know which distance should be used If I want to raise
>two inverted V dipoles for 40 and 80 (both with the apex angle of 120
>degrees). I am trying to find out the right distance in order to
>minimize interaction. I believe that the 80 meters dipole must be on the
>top. Is that right?
Aloha Carlos, I have 160, 80, 40 and 30 meter parallel dipoles,
all fed by a single 72 ohm twin line. The ends go down to various
trees, usually with rope to complete the span, and a couple
to push-up masts. There is going to be interaction among/
between parallel dipoles. Yes the longer ones should go on top,
because their wires are longer. In my inverted V's, I left
extra wire on the ends tangling from the tie-off ceramic
insulators. The closer to the ground the ends of your V's
get, the more extra length you will need to resonate out
the ground coupling capacity at/near the ends of the wires,
and, also as they cannot help but be close together at the
feed points, you will need the ability to trim the lengths.
You will find that whatever you do to one of them WILL effect
the other. So, if you are aiming for exact frequencies for
1:1 vswr, you will be doing a LOT of fiddling with lengths.
It is a fun, but can be frustrating project if you are going
to be frequency fussy!!
73, Jim, KH7M
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