Probably the best answer is that it's a waste of time, depending.
The principle amount of gain from a two/three element element yagi
(either kind) is taking as much of the radiation from one side and
forcing it to the other. The rest is from squeezing (narrowing) the
pattern in the wanted direction
A dipole at height is really a very good antenna, simple.
The "depending" above relates to whether your opposite targets fall
within a narrow range. This is almost never true for a field day,
where omni coverage is important.
On the east or west coast, two/three element yagis do well because the
unused direction (ocean, principally) has no field day participants to
speak of and they are close in.
For what you seem to be proposing, look up a W8JK bidirectional, which
is a field day favorite.
If you want to invent new antennas, getting your feet wet in modeling
is a must. There are a very many non-intuitive ways that antennas act.
PS, to post on the reflector normally, you need to subscribe. See the
URL at the very bottom of this email.
73 & GL
----- Original Message -----
From: <N7DC@cs.com>
To: <antennaware@contesting.com>; <dx-qso@yahoogroups.com>
Sent: Saturday, May 25, 2002 2:53 PM
Subject: [Antennaware] weird question
> Any of you antenna gurus out there ever tried a simple dipole, with
a
> director on each side of it? In other words , string a dipole, then
place a
> set of directors, parallel, and on both sides at once? I havent
been able to
> make head or tails of these antenna design software packages, guess
I need to
> set in a class to actually see one work. What I have is temporary
loops
> installed for 17 and 12 meters, and have constructed "director"
dipoles which
> I have hung on verticle bamboo poles , just in front (facing East)
of them.
> Appears to be working better than just the plain loop - for that
direction of
> course. But, am wondering if I can get bidirectional antennas out
of them by
> hanging two such directors. Dont want to go thru the "phase switch"
method
> etc. Just experiementing to see what I can use on field days, scout
> camporees etc.
> Thanks
>
>
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