Do you think this is a good antenna array for my cb?

[06hyperion]

I haven't hooked my cb up to it yet.. but do you think the two antennas would interfere with each other? Do you think I should run another cb for the second antenna? I want to put some ham radio antennas on there when I get my license.. Is it a good idea to have all these antennas on one mount?

Is there a way to bridge them?

Any questions, comments, or suggestions would be appreciated.

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[94Cruiser]

Just looks unstable

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[06hyperion]

Just looks unstable

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I haven't secured it yet.. will probably put a spring extension at the am/fm base.. and either weld it to that, or tighten it up so I could untighten it when I need the change trucks.

Want to put at least 8 antennas in the middle.. maybe some on the outside as well. Just getting ideas together and seeing what would work.

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[06hyperion]

Just looks unstable

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Here's a few pics. I want to put 6 more mounts on there, 8 total. I also put a shorter antenna on there and plan on keeping the others around the same size.

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[Flipper]

Antenna 101: there a two parts to an antenna a negative and a positive. The positive is the “post” or element the secound is the ground this is the mounting base and the vehicle itself that makes the negative part, all elements are a specific length to corrispond to the frequency recieved and transmitted. Your mounting configuration is mounted to the positive side of your am fm radio with no true ground or connection to the car, basically you are shorting the am fm antenna through the ground in the cb radio the way you mounted the base. Your antennas should be as far away from each other as possible. Mounting the antenna to a good ground is the most important thing or they will not work correctly, yours basically have no ground. I am trying to keep to the basics because there is a lot more involved but your mount and theory are way off and will not work. Im not trying to hurt your feelings but I would trash the whole idea. If you need any help or suggestions feel free to ask, I would be glad to help.

 

[06hyperion]

Antenna 101: there a two parts to an antenna a negative and a positive. The positive is the “post” or element the secound is the ground this is the mounting base and the vehicle itself that makes the negative part, all elements are a specific length to corrispond to the frequency recieved and transmitted. Your mounting configuration is mounted to the positive side of your am fm radio with no true ground or connection to the car, basically you are shorting the am fm antenna through the ground in the cb radio the way you mounted the base. Your antennas should be as far away from each other as possible. Mounting the antenna to a good ground is the most important thing or they will not work correctly, yours basically have no ground. I am trying to keep to the basics because there is a lot more involved but your mount and theory are way off and will not work. Im not trying to hurt your feelings but I would trash the whole idea. If you need any help or suggestions feel free to ask, I would be glad to help.

Yes, i definitely need some suggestions. I haven't gotten my license yet, or bought any radios/antennas other than my cb. I like the mount because it would leave me a lot of room for other stuff on the rooftop. I want to get a multi band unit.. hf-uhf cw/ssb/am/fm and leave some space for other stuff, like sat uplink, rf receiving antennas, etc. Where is a good spot to ground? The mount is no good? How would I repurpose it in that case?

Thanks for the help.

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[Flipper]

Yes, i definitely need some suggestions. I haven't gotten my license yet, or bought any radios/antennas other than my cb. I like the mount because it would leave me a lot of room for other stuff on the rooftop. I want to get a multi band unit.. hf-uhf cw/ssb/am/fm and leave some space for other stuff, like sat uplink, rf receiving antennas, etc. Where is a good spot to ground? The mount is no good? How would I repurpose it in that case?

Thanks for the help.
Glad to help. 1st the ground is the whole metal part ot your truck, engine, body,frame. Your mirror mount antennas would usually be attached to metal mirror mounts that are on a truck these mirror mounts are screwed to the body making the connection from the base of the antenna, the negative, to the body of the truck, a magnetic mount antenna connects the ground through the magnet to the body of the truck. When you get into HF you can connect ground straps from the frame to the body just to make the ground connection better. NOTE: the positive post or element cannot touch the ground or you will fry your radio when you transmit. Now if you would mount your antennas on your roof rack at each corner the roof rack would have to be attached mechanically to the truck or the only thing you are going to have for a ground is the rack, basically you would “ground” the rack to the truck , then the whole truck would be the negative or ground. More ground the better. There are many options you just have to make sure your antenna base is connected metal to metal to the truck.
Antenna height: higher the antenna the more range.
Next is the length of an antenna, ALL antennas are designed for a certain frequency, am/fm is 30”, CB is 102” this is usually wrapped around a fiberglass pole. So you have a 4 ft fiberglass mast with 102 inches of wire wraped around it. You get the idea, it gets a lot deeper but lets keep to the basics. This length has to be exact in a transmitter, this is called the SWR or standing wave ratio. To do this adjustment you need a SWR meter , borrow one from a friend because this is usually a one time thing. Your friend can show you how to do this, it is really easy so dont be overwhelmed. This is where a good ground is important or you wont be able to get the antenna within spec so if it is to far off you will have terrible performance from the radio or if really off it will fry it.
Antenna placement on the truck. All antennas transmit or project a pattern, probably the ideal place would be in the center of the roof so you would have a even amount of metal (ground) on all sides, usually this isnt practical so where you mount it is going to be a compromise but that is just the way it is.
Hope this helps, any questions let me know

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[94Cruiser]

Antenna 101: there a two parts to an antenna a negative and a positive. The positive is the “post” or element the secound is the ground this is the mounting base and the vehicle itself that makes the negative part, all elements are a specific length to corrispond to the frequency recieved and transmitted. Your mounting configuration is mounted to the positive side of your am fm radio with no true ground or connection to the car, basically you are shorting the am fm antenna through the ground in the cb radio the way you mounted the base. Your antennas should be as far away from each other as possible. Mounting the antenna to a good ground is the most important thing or they will not work correctly, yours basically have no ground. I am trying to keep to the basics because there is a lot more involved but your mount and theory are way off and will not work. Im not trying to hurt your feelings but I would trash the whole idea. If you need any help or suggestions feel free to ask, I would be glad to help.

Plus...... it's going to do a reasonable impression of a spinnaker

Again, not trying to hurt feelings :-)

 

[06hyperion]

Plus...... it's going to do a reasonable impression of a spinnaker

Again, not trying to hurt feelings :-)

That might be aesthetically pleasing, depending on how it curves.

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[06hyperion]

Yes, it helps.. but isn't the am/fm already grounded? If it's secured to the am/fm base, then wouldn't it be grounded also?

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[Flipper]

Yes, it helps.. but isn't the am/fm already grounded? If it's secured to the am/fm base, then wouldn't it be grounded also?

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Yes, I cant tell by your pix, in the one it looked like center of your mount was touching the shaft of the am/fm ant.
Antenna 102
Antenna transmit pattern. You are going to hear a term db or decible. Stand in the middle of a room and put you arms out like you were an alligator chomping up and down. When your arms are open the whole way lets say that is 3db now with your arms still out and open turn in a 360 degree circle. Now when you went around if you were the antenna everything in the “V” going out if you were transmitting is what a receiver is going to pick up.
The wider the pattern the more recievers will hear you, now the drawback the wider the pattern the shorter the distance you will transmit
So now shut your arms half way and do your turn. This would be a 6 db gain , you are going to transmit farther but your “V” will be half so not as many recievers will hear you but the ones that do will also be farther away.
Arms 3/4 shut .... 12db now you have a very narrow pattern but it will go alot farther. Its a trade off if your antenna has a real narrow pattern and the thing is waving all over the place when you are 4 wheeling no one is going to hear it when the pattern is aimed up in the sky or down at the ground.
This is why walkie talkie antennas are a really really low gain so they transmit a pattern all around so you could be standing on your head and they will work.
Next radiation: When you transmit the energy just like a ray gun the db gain narrows or widens the beam. The energy or radiation is very dangerous stuff . It causes cancer, and can severely burn you. You DONT grab a HF antenna and key the mic. You will do that once, it will be about 10 times worse than sticking your fingers in a wall socket. The closer to the antenna the higher energy, with your antennas that close to each other and you transmit especially with the 2m or HF they are going to bleed into the other radio recievers.,Being that close could even possibly damage the recievers. You want to keep antennas as far apart for one another as possible.
Another issue you are going to have is wind resistanse and tree branches. It would just be a matter of time before you yould tear the antennas off.

 

[Prerunner1982]

Forget the dual CB antennas, they need a 1/4 wavelength (108") separation to work well. Even if hooked to 2 CBs it will cause tuning issues and could damage the radios.
A CB and 2m antenna may work in that configuration as I have seen many people run both on an Arizona Rocky Road antenna mount, which isn't the best place for a CB antenna but that's slightly off topic here.

 

[06hyperion]

I found something to use as an extension.. And will probably use the short antenna. I may just call a steel fabricator and get them to rig something to the entire body. I'm not sure.. Here's a few more pics. Thanks for the suggestions.

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[06hyperion]

I found something to use as an extension.. And will probably use the short antenna. I may just call a steel fabricator and get them to rig something to the entire body. I'm not sure.. Here's a few more pics. Thanks for the suggestions.

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[Prerunner1982]

A simple fender mount would be sufficient, cheaper, and offer a better ground plane.

 

[TOMB]

From the Firestik web site.

11. If you mount two or more antennas close to each other, you will alter the transmission patterns of each one. The affect may be either positive or negative. We recommend that a minimum of 12" exist between your CB antenna and other types of antennas.

I remember reading a minimum of 15" someplace, but couldn't find where.



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[egpowers]

Get a simple fender mount and run one antenna, it's not really needed to run dual antenna. In this pic, you can sorta make out the mount I have for my antenna, it bolts to the inside of the fender and comes over the edge, I run a single 4' metal antenna and have no problem getting 2 to 3 miles range transmit, and 5 to 7 mile range receive, it's also across from my radio antenna. My HAM antenna is a mag mount on the roof for my handheld.