Directional Antennas

[GREGT]

So like most people here I am looking to spend as little money as possible and get as much enjoyment as I can. I have been looking, but cannot seem to find where there is a good explanation as to the advantage of having vertical elements on beams? My preference would be to have a single tower with an omni directional on top while using a horizontal beam set as a ground plane. What is the advantage of the vertical elements on the beams??? I cannot seem to find anywhere this has been explained.

[nosaj]

Being able to use them together with beam as ground plane or to use them separately. to take advantage of the directionality. Or to recieve horizontal or vertical signals.
Maybe this article will help
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nosaj

[MDYoungblood]

So like most people here I am looking to spend as little money as possible.

You really haven't been in radio very long.

I have been looking, but cannot seem to find where there is a good explanation as to the advantage of having vertical elements on beams?

Horizontal polarity has less noise than vertical.

My preference would be to have a single tower with an omni directional on top while using a horizontal beam set as a ground plane.

Good idea, this is a popular setup even in the ham community. The omni gives you local communication and the beam,distant.

What is the advantage of the vertical elements on the beams??? I cannot seem to find anywhere this has been explained.

The beam is for talking long distances to other stations with basically the same setup, when propagation is active, a horizontal signal bounces off the ionosphere at a better angle than a vertical signal, in theory at least. Also they reduce the noise from behind the antenna.
Vertical polarity is better for communicating with similar polarity antennas which is most of the CB world, almost all vehicles are vertically polarized as is the same with most omni base antenna.

3's

Greg

[GREGT]

Please bear with me as I've read the article, link, listed above so thank you for that. Currently I do not own a beam antenna so how does one that has both vertical and horizontal elements work? Do you have to switch polarization? do they send and receive both vertical and horizontal polarization waves automatically? I need my ground plane for omni directional signals and would love the horizontal beams for gain and distance. I guess I will lose some advantage of long distance vertical polarization, but I'm not sure if that is a huge deal as I will still have my ground plane almost 80' in the air for most local signals.

[MDYoungblood]

A dual polarity beam will require 2 coaxes running up to the antenna and a switch to change polarity, preferably one that grounds (shorts the unused coax to ground). Nothing automatic about a dual polarity beam, if there was such, it would be very expensive.
Another thing is with a beam antenna you aren't totally rejecting signal from the back and sides, just reducing it.
You could always mount the omni in another location, away from the beam.

3's

Greg

[GREGT]

I do have two towers a 32' and a 48', neither of them are up yet. I am just trying to figure out how much I will loose if I just run horizontal beams, a ground plane, and the 48' tower. I could also have the dual polarity beam, but them I need to use my 2nd tower. One tower would not look to crazy in my yard, but two probably would. I don't know maybe crazy is good.

[jessejamesdallas]

I do have two towers a 32' and a 48', neither of them are up yet. I am just trying to figure out how much I will loose if I just run horizontal beams, a ground plane, and the 48' tower. I could also have the dual polarity beam, but them I need to use my 2nd tower. One tower would not look to crazy in my yard, but two probably would. I don't know maybe crazy is good.

You don't need both a horizontal beam and a dual polarity beam...Unless one of the beams is for a different Band of channels like 2 meter, or something.

I have a MaCo Shooting star beam which is a 4 element horizontal/vertical antenna which lets me talk locally and DX...There's 2 coax runs to the antenna like MDY mentioned and a switch to switch back and forth from the two polarizations.

Also depending on how many elements the beam has, determines how directional it will be...A 2 element beam for instance is going to have a fairly wide signal pattern to the front and sides, but not allot out the back...A 4 element is still going to have signal off the sides, but more towards the front...When you start getting into the 6 and 8 element beams your mostly just going to have signal out the front where your pointing and very little off the sides...One advantage of this, is you reduce signals coming in from the sides so the channels will be a little quieter and whoever your talking to will come in a bit louder...disadvantage is you will be missing out on hearing guys off the sides that maybe trying to contact you!

Lots of guys run just a horizontal beam with a omni antenna on top, but it's not for any ground plain effect off the beam, it's so they can talk local off the omni, then switch to the beam for dx.

[GREGT]

Thank you, I was planning on using a horizontal beam being a 7 element Maco M107C and that is why I wanted the ground plane too.

[jessejamesdallas]

Another thing to consider when stacking antennas one over the other, is the towers wind load rating...if you have more antenna on top of the tower than what the tower recommends and a strong storm pops up, it could make for a bad day...

[GREGT]

Yes indeed, I still need to do a little more research, but with the addition of guy wires I'm pretty sure life will be good. Trust me, I will check at least 3 times. I certainly do not need any more problems.

[jessejamesdallas]

Yes indeed, I still need to do a little more research, but with the addition of guy wires I'm pretty sure life will be good. Trust me, I will check at least 3 times. I certainly do not need any more problems.

That's what I ended up having to do...I knew my antenna + the rotor was going to be pushing the limit recommended for my "free standing" tower, so I added guy wires...Been up now since 2013 and through some storms just shy of being tornadic, and the thing has never budged...

[MDYoungblood]

Thank you, I was planning on using a horizontal beam being a 7 element Maco M107C and that is why I wanted the ground plane too.

I've never seen anyone put up a 7 element beam by using a fold over tower,, that would put a lot of stress on the antenna's boom. Best to install the tower permanent and rent a manlift to install the antennas.

3's

Greg

[GREGT]

Yes, the tower I have is the lower 48ft section of a 80' tower. The base is very wide and is considered a free standing tower requiring at lease 6 yards of concrete and a 4' deep hole. I did plan on using a man lift to install it. Guy wires would just be for a little additional safety.