Forward power and reflected power and transmitter and antenna matching

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These last two pictures is the way they come in the box.
There are two pipes tied to the bottom that come off and connect vertically. Horizontally if you want.
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Go back to the maker and ask questions!
 

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post#21.
The problem with mounting two antennas like that: At the point of the camera you will get a gain of 2. Lets say the camer is north of the antenna. So N. and S. will get 2X. But East/West you will get near 0. (this assums the elementy are 1/2 wave appart) If the elements are some othere distance appart then the patern will be strange. I can predict if I know the distance.
 
I did ask the guy I bought these from, but I doubt he will be more knowledgeable than you guys.
 

Just a reminder, they are four antennas, NOT two. I only showed two because I'm not the best at drawing.
 
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http://www.labelitaly.com
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Ask them for information. Do not say you have the antenna, say you want to buy!
Last night I found this antenna under a different name. They had a online manual. I could not stay connected long enough to get the manual downloaded. Now I can not remember the name.
 
I didn't ask yet. But it does say here in this package:
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that you need four antennas. And like the other website, it also says the polarization is vertical.

So, when four are used....how are they mounted? I'll see if they will answer me.

And this is the 4-way splitter I was talking about:
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They also say 4 antennas are used to increase range without increasing power:

>>ideal for feeding an array of antennas to allow you to increase your coverage area without having to upgrade your transmitter power.
Standard models are 2-way, 4-way, 6-way, and 8-way dividers. Others available on request.>>
 
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It lists all the parts in that advert, and a single aerial is shown in this page:



Presumably that's showing how it's mounted vertically?

It doesn't say it 'needs' four aerials, I imagine it's specified with four in order to handle the much higher power transmitter.
 

As far as I'm aware, you stack them vertically above each over, at the correct distance, and connected via a suitable phasing harness.

I suspect you may do well to read this, particularly page 32:
 

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From my little search in google, it sounds like I should do something like this:
 

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I suspect you may do well to read this, particularly page 32:
A very interesting document, thank you for posting it.

However, there is a possibility that the guy who wrote it is an idiot and does not know what he is talking about!
(There are many references to that unit which some of us believe should be abolished!).

JimB
 
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Well, I think I found some mistakes in it. I'm in page 33 now.
 
Thank you Nigel, I see from post 11 we have what is on page 34 BUT you are driving the elements in phase not out of phase so the signal will be strong up/down and week N.S.E.W.

I have used what is on page 32 many times. The elements are driven in phase. The length of the coax is the same for each antenna piece. Or they could be 1 wave length different. In my applications each element is delayed by 1 wave length. I ran the coax up the tower and "T" out every wave length. Some antennas are "T" out at 3/4 wave length.

If you look at page 31, For a vertical antenna. The graphs on the left is seen from the top view. 0=north, 90=east, 180=s, 270=west. Page 34 shows power in all directions. If you look at your antenna it shows the south is 1/2 of north. South is the direction of your pole. So face the antenna toward the most people and the pole side the direction with the least people.

Page 31 left side graphs. Top graph; 0=up, 180=down, 90 & 180 is to the horizon. This is for 1 element with a gain of 1.
Page 31 left side graphs. Bottom graph; 0=up, 180=down, 90 & 180 is to the horizon. This is for 4 element with a gain of 4. The signal at 90 and 180 is 4x stronger. The signal at 120, through 180, is much much smaller and that is good. (4 elements 1,2,3,4 up/down the pole)
 

I was ganna say what do you guys understand from page 34. You caught it. But I'm not sure I understand what you want me to do now. Can you please re-phrase in simple english?
 
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