Hey I have my truck now and i want to mount dual fiberglass CB whips in the bed of the truck (up against the cab) because i have sport mirrors on it and i was just wondering what kind of mounting bracket you guys use for that and where i can get them, thanks

 

Don't know about the brackets, but I am assuming you are going for looks more than performance? And if it is for looks, you might be better off only running one, and using the other as a dummy, and not hook it up.

 

Hello, don't use the aluminum antenna brackets. Go for the steel ones, you can usually find them in chrome plated too. The reason is that the aluminum sets up an electro-chemical reaction that causes your antenna connection to corrode. The higher power output of your CB the faster it will happen.

If you go with dual antennas mount them as wide as possible. On a regular fullsize pickup the bed is just wide enough so you will not see too much transmission strength losses. Any closer together and the antennas will be fighting each other when you transmit.

Try not to mount the antennas up next to the cab of the pickup. If you can mount them with say, 6 to 12 inches of empty air space from the cab the antennas will perform better. Also, the cab acts as an effective block of forward transmission so the more antenna you have sticking up above the cab the better your transmission to the front will be.

Don't rely on the bed to provide a good ground. Run a ground wire from one antenna bracket to the other and then to the frame of the truck.

And lastly, after everything is installed, but before you key up the mic, take your truck to a CB shop and have them tune the antennas. This will adjust the SWR (signal to wave ratio) which makes sure that your antennas are transmitting as much as possible. I won't go into detail but if your antennas are severely out of adjustment it can damage the CB radio. Don't believe the "pretuned" antenna lable either.

Also if you havent bought the whips yet, get the Firestick2 antennas (www.firestick.com). They have a built in adjustment bolt at the end of the whip that makes tuning the antenna super easy. Most other brands require you to cut little bits off the end of the whip to tune them, ouch.

 

You can get the brackets from Radio Shack. Follow aelliott's advice and you'll be fine Thanks to him/her? I don't have to type all of that out

 

most of the time the mounting equipment comes with the whips. i got my whips at radioshack for 50 bucks, came with the 4 footers, coax and the mounts. surprisingly they work great. i like the way they look too. mine are mounted to the front of my toolbox

look at my gallery if you wanna see em.

 

Franklin2 is on the right track. Don't use 2 antennas. All it will do is give you a messed up radiation pattern. In theory, two antennas will transmit no more power than one. However, they actualy transmit less because you are transmitting through twice as much cable. Cable is lossy.

 

Here read this and decide for yourself if you want single or dual.

 

marineman227 / ZombieSlayer-
Note that is a Firestick website. I'm sure they would be more than happy to have people purchase two antennas instead of one. They are correct about the frontal and rear lobes, but unless you are driving a big rig, this configuration just isn't practical due to the space required between the radiators. It can be done, but it aint practical and you will lose total ERP due to transmitting through more (up to twice as much) cable.

PS True perpendicular co-phasing occures at about 18ft of seperation on the 11 meter band. Anything much less than that will give you a lot of 'wasted' side lobes.

 

Yes I know it's firestumps website. I was just trying to give the guy some more info without coming off like a smart ***.

I wouldn't call myself an expert, but I have at least a decade of experience and do know what I'm talking about.

One of these days I'll get my 10 meter license.

 

Cool man.

 

I have to agree, two antennas will do nothing for you.

I would drill a hole in the roof and go with a Wilson 1000 or 5000

 

i disagree, dual whips have worked great for me and they are only the width of the bed apart.

 

thanks for all the good advice guys, When i started this post i knew nothing other than the rumor that the dual antennas would have much better transmitting power. Now that i've read some of those things i might just leave one as a dummy antenna because i do like the look of those duals but i'll go find a cb shop and see what they recommend. I didn't even know such a place existed so if there's someone who can do it and do it right and make it work then i'm all for spending the little extra money. By the way i am looking mostly at forward and back transmission because i like to call ahead on the highway and see if there are any speed traps ahead and also call them back to people following me. The other time i really use my CB is offroading when generally my buddy is less than 100ft behind me but we're in a place where cell phones have no reception. I want to be able to transmit to the side somewhat but it's not as important to me as front and back. And as far as the cab blocking the forward transmission that's why i'm looking at 5 foot whips because those i think would be about as far over the top of the cab as alot of the smaller magnetic mounts that i see people have mounted on top. Thanks for all the help guys and i'll let ya know what i decide to do

 

Just about any truck stop will have a CB shop.

I am really into CB's I have a just over 750 watts running out of my truck. I have tried just about every antenna, in every spot.

It is all about SWR's get them as close to 1.1 as you can.

My radio does 16 bird watts,plus a 5 pill kicking it. You will find that once you get into it you will find your self spending $$$$$$$$$$ it is not cheap.

I still like the Wilson 5000, it will handle plenty of watts and the stinger will bend if you hit a tree branch or something. Where a high coil antenna will rip right off of your truck.

If you go to the CB shop check into a supertune they are about $30-$45.00. You will find a big difference in the handling of your radio.

http://pub86.ezboard.com/bworldwidecbradioclub
Check out this site you might find some good info here.


If you do get into it let me know, i'll give you a yell from my house. My base does 1000 watts on a tube kicker. I have to be careful when talking on that when it is cranked up because i'll come through my neighbors phones, and TV's. Plus i will turn on my neighbors touch lamp inside his house.


But read that site and you will see that in this case one is better than two. Like I said it is all about SWR's and placement of the antenna.

 

Power can be a big money trap.

Getting range from power can be figured roughly by anyone with a cheap calculator. To double my range I'll need to increase my power by a multiple of ten. So, if I'm getting out 3.5 miles with my 4 Watt CB, I would need 40 Watts to get 7 miles. Now I've gone 7 miles, I'll need 400 Watts to get out 14 miles. 14 is not enough, so I'll buy a 4kW PA to get out 28 miles. It goes on and on.
Where did I get my initial 3.5 miles on 4 Watts? I took out my cheap calculator and figured the antenna on my truck is 2 meters high. Then I punched in Square Root (17 x 2 meters), the seventeen is a constant. That gave me 5.8 Km, so I converted it to about 3.5 miles. This is for flat ground.

That's a simple, fun formula. Think about it. If I drove my rig up on a 200 foot hill my little 4 Watt radio would reach about 20 miles. I would have to spend quite a bit of money to power my way that far.

It's a dirty little secret that the folks that build and sell linears don't want me to know. They rip me off and who will I complain to? Gee, it is illegal to use over 4 Watts.

I'd like to, but I can't change Physics. Optimum distance on a twin stick array is a half wave at 18 feet apart. 14 feet is minimum for anything resembling increased gain.

I hate to come off on this giving myself a bad impression to everyone, but it just pisses me off seeing reputable companies selling, "high power," this and that. Twin sticks that can't work, (Oh, they tell you they've got them to work at 4 feet, but don't tell you how or show the results.)

The way to judge an antenna is by it's gain figure, (for a mobile anything from 1 - unity, to 3dB is great), and from it's frequency response, (how low the SWR is over all 40 channels, not just channel 19). The best one out there is still the 1/4 wave 109" - cheap - stainless steel whip.

Vent over.