Beams with v-5000 on top

[153]

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I am currently running a set of maco 5's. (vert) If I was to put my v-5000 on top via mast so that the antenna was not in the path of the beam would that work? My beams currently hang down into my towerby a couple feet, so I figured if the tower don't effect it a small mast continuing up through them should not. Is this correct or not a good idea. My beams are so tight I really need the v-5000 to hear allaround at times. Can anybody tell me if this will work?

[drdx]

If you put a vertical omnidirectional cb antenna up above a vertical cb beam it will be directional. Notice I said CB and CB. You can put an antenna for another band up there, like 2 meters or something, but not a cb one. Not as directional as the beam, but directional. The vertical will use that beam as a groundplane and being a beam it is not going to offer omnidirectional results. Unless you use that vertical beam for local a lot, your best bet is to use that beam flat and put the vertical on top. -drdx

[Circuit Breaker]

That should work just fine. The mast will skew the radiation pattern and gain a little. It may even change the SWR, but you should be able to adjust the antenna to bring the SWR down again if it changes.

[linx]

If you put a vertical omnidirectional cb antenna up above a vertical cb beam it will be directional. Notice I said CB and CB. You can put an antenna for another band up there, like 2 meters or something, but not a cb one. Not as directional as the beam, but directional. The vertical will use that beam as a groundplane and being a beam it is not going to offer omnidirectional results. Unless you use that vertical beam for local a lot, your best bet is to use that beam flat and put the vertical on top. -drdx

There's the key. Install the beam horizontal and put the vertical antenna on top of the horizontal beam. You'll have much better success talking skip on a horizontal beam anyway...plus you can put the horizontal beam a few inches out of the top of your tower and not have to worry about the pipe bending in a high wind. I had a Moonraker 4 @ 15 ft above my tower on a mast. Never again, lol. Too many sleepless nights in storms. My current beam is horizontal and 1 ft out of the top of my tower. Bring the wind on.

[153]

Ok so let me understand ...if i put my v-5000 on a mast that extends above my vertical beam it will make the v-5000 directional? I do not talk skip too often as much as I try to talk local. Now I mean local being within a 150 miles.

[drdx]

Yes. I've ran a vertical(in my case an antron) on a 10 foot mast above a moonraker 4 and it was very directional and that's one element less than what you're running. I've seen it happen to others too, but every install is different. I guess distance above may make a small difference(i wouldnt think it would, the beam would still be a vertical ground) but as linx mentioned the wind load and leverage on that mast and rotor ( I hope you run a thrust bearing) gets ugly. -drdx

[Circuit Breaker]

I don't think so. Your ground plane antenna should ignore anything below it. Even if it "saw" the beam, I don't see how it will make it directional because your vertical radiator is above the vertical radiators of the beam...and what gives a beam a directional pattern is the reflectors and directors. These will be below the ground plane antenna and really should have no impact on it.

[drdx]

I think we're double keying there. -drdx

[153]

That was what I was thinking. I did not "think" the beam would "see" the the gp as long as it was above the elements on beam. But I do know sometimes things do not work as planned.

[Circuit Breaker]

I believe so.

I wonder if an Antron 99 is more susceptible to having a directional pattern because it has no ground plane as it is.

[drdx]

If that vertical had its own radials I'd think you'd be safer but just as in a vehicle, where the ground plane is below the antenna, it effects radiation pattern. Now my antron was a half wave, maybe a 5/8 is less susceptible to ground plane effect from the vertical elements. Sure the vertical is above the beam, but the mast the vertical is on will be carrying signal as well. Try it, I'd love to hear what you find out. -drdx

[153]

Thanks for all the advice. My tower is kinda tall so i am not wanting to have to experiment...but looks like I will anyway. My v-5000 does have ground radials. maybe that will help

[drdx]

So, if it is directional, you would not want to use that vertical above a horizontal beam that I mentioned at all. The additional radials of the ground plane may skew the pattern of the beam as they are too horizontal. Man, that's a lot of windload, but cool setup. Don't buy a 2nd run of coax when you do that, go with a remote coax switch, that uses just one run of coax that also acts as the control cable, as it will save you $$$. -drdx

[Circuit Breaker]

I would say try it and see. Put it up...listen to someone while using the ground plane and then turn the beam. The signal shouldn't change is the ground plane is not being affected by the beam. I know that a vertical more than 1/4 above ground really only needs two radials to be 90% efficient and have a fairly omni-directional pattern. Most ground plane antennas only come with three radials...some with four.

[153]

Well i am going to keep my beam vertical with no chance of horiz. I may opt for a standoff and that will still get my v-5000 at about 60 feet to the base.

[231]

So, if it is directional, you would not want to use that vertical above a horizontal beam that I mentioned at all. The additional radials of the ground plane may skew the pattern of the beam as they are too horizontal. Man, that's a lot of windload, but cool setup.

This was my first thoughts, too. I'd be more concerned about the beam pattern being affected than the ground plane. I always ran the beam more than the ground plane. But not everyone does so it might not be a big deal to some. But I agree, that is alot of wind load on the mast.

[153]

k well that ends it for me. i do use the beam more and love it. I think i will hang the groundplane off the side of my tower below my elements and let her ride:)

[drdx]

Offbeat, but here's a plan if you're tired of having to spin that beam around to much but want to keep it. Get that remote coax switch(mfj 4 antenna model, probably $129, as cheap as that vertical) and mount it at the top right at the beam. Then, install 3 or 4 half sloper antennas, on in each direction, running from the top of the tower. That way, you have the beam, and another semi-directional system of 3 slopers that you can instantly switch around, creating effectively an electronically rotatable system, kind of like an old superscanner. Each sloper is its own antenna and when you switch to any one sloper, the rest acts as a reflector and it is slightly directional. When you're switched to your main beam, the owhers are grounded out via the switch. The slopers are just wire and you can do half slopers or full ones, your choice, but a cool approach and definitely different. -drdx

[Circuit Breaker]

Wouldn't they only be reflectors if they were a certain wavelength away from the one transmitting?

[153]

whew. you totally lost me.....i'll take your word on it but too far out my reach. I just was trying to eliminate 2 towers. Will the v-5000 work on a standoff fairly good?

[drdx]

The distance wouldn't be as big a determiner as the fact that their length plus the coax that feeds them would offer loading to make them reflectors. There is a nice article using full slopers on this in the ARRL antenna handbook where a guy did this on a lower band and had nice results and I think 5 slopers setup. Switched to one, the rest and their coax (adding the 5% needed to be reflective) grounded out made it work. This is very simple and would use your same tower there 153. Even with no thought put into the reflector at all, a sloper has a few db of directivity in the directon of the slope, I'm guessing due to the tower. A 2nd sloper benefit is the high feed point, offering nice low angle local and long distance dx coverage. -drdx

[231]

whew. you totally lost me.....i'll take your word on it but too far out my reach. I just was trying to eliminate 2 towers. Will the v-5000 work on a standoff fairly good?

It should work, but you'll likely still have a null towards the tower...if only a little. It might not even be noticeable. What I always did was run the ground plane lower and away from the beam (as much as possible) as not to interfere with it's pattern. I used it primarily to find out if the beam was in the right direction or not. Sometimes I'd use it for someone really close, but for the most part the beam was the primary antenna for me.

I have a remote switch box too. And if you decide to run one, you won't be disappointed. But much of that depends on how much coaxial run you have. I paid about $230 for my ICE 9 position switch box, not including cable. But it has 7.5kw rated relays. So how much wattage you are running will probably determine which to go with. Some of the less rated ones (like MFJ) are alot less money but are usually fine for most folks.

[unit199]

I'd just go for it man...
I had installed an Antron 99 above a MACO M-103C 3 ELEMENT and I also had an antenna switch to change between the two.
I LOVED having that rig.... Dang I miss Country livin..... break break,,,,, aaaaand i'm gone.

[Red Warrior]

I would recommend a different approach entirely. Get a 4 element cubical quad that can be switched between vertical and horizontal. Point it in the general direction of your most frequent QSOs and set it vertical for local talk. Then when skip rolls in, switch it to horizontal. You will get much higher gain than a flat beam and it will work just fine for local talk off the sides and back.

I have a guy barefoot about 20 miles from me that talks to me off the back and sides all the time.

[153]

OK I didn't want to admit to this but my beam has only one purpose in life. There are certain folks around me that on fri or sat night get beered up (nothing against beer) and talk very very nasty. So when I key up i dust their pants and speak my peace. If I dont want them to talk they don't talk. I'm not being mr big and bad but there is folks around my area that has their radio in the house and kids around. I think radio ought to be fun for family also. It just gets under my skin. We are all in the same area but my 5's are tight enough that I can't hear a station out of any of the corners. I just really did not want to have to get into details or open a can of worms.