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Alabama Buckeye
04-06-2022, 11:52 AM
Please tell me the ground truth what is the purpose of having multiple director elements on a Dipole, a Yagi?

Alabama Buckeye
04-06-2022, 11:54 AM
It is beyond me why more than one is necessary? Pinpoint accuracy?

JesseJamesDallas
04-06-2022, 05:52 PM
Directors force more of the signal towards them, making the antenna more directional in that direction...more directors you have, the more forward gain you get...

Add a reflector behind the driving element and you will cut out allot of the signal coming in (and going out) the back side.

side note...the more directors you add, the more forward gain you get, but at the same time your out-going signal pattern will get more narrow...An example would be like if with just one director you can talk to the whole East Coast from like Texas...then if you add 2 or 3 more directors then who ever your talking to will hear you louder, but instead of picking up the whole east coast, you would only be able to pick up maybe one or two States in the direction your pointed...

That make sense?...sounded right when I was thinking about it anyway.:300 (96):

Bobcat
04-07-2022, 01:01 PM
A theoretical "isotropic" antenna puts out a given amount of RF antenna in ALL directions.

A directional antenna uses passive elements to "bend" or "force" that RF radiation into a desired pattern.
When speaking of "gain" .... an antenna doesn't "put out any more" power...... it simply uses these extra passive elements to "pull the RF emission shape around so that it is more concentrated in one direction. THAT is where the "gain" comes in.... is the concentration of available RF power in a specific direction.

One director... will focus it a little bit.
A second director.... will it a little bit more.
A third director..... yet a little bit more.

Each that you add causes a narrowing of the transmitted beam.....but the concentration in THAT direction is stronger... giving more gain and sensitivity.

Alabama Buckeye
04-09-2022, 07:52 PM
In other words, you have to really have to work at it to narrow down the azimuth for those with whom you regularly have intercourse with; and, log your contacts.

Bobcat
04-11-2022, 05:15 PM
Well.... the more elements.... the more your antenna "focuses" in the forward direction.... so the better you will reach them....and the better you will hear them.

mjd420nova
04-11-2022, 09:38 PM
I used to use a long john five element beam mounted horizontal with a big stick in the middle. Was able to get directional use from the omni big stick by grounding the driver element for the beam.

Alabama Buckeye
04-13-2022, 10:41 PM
:300 (20):Five element beams are normally mounted horizontal, what special about your long john? How to you get directional use from the big stick? Grounding the beam driver element, that's a new one for me.

Bobcat
04-14-2022, 06:46 PM
Sticking my nose in with a WAG........

Grounding the driven element on the beam would essentially make the whole thing ground.
Mounting the vertical "in the middle".... I would think that the "beam" would act like a
"directional ground plane" and distort the omnidirectional pattern of the vertical antenna...making it project a little further in the direction of the beam.

Again... only a guess.......