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firehawk
07-01-2009, 05:38 PM
Ok, I haven't messed with a CB radio since the middle '70's. What is involved in setting one up? I'm sure it's more than just mounting an antenna, attaching it to the radio and talking. What's involved with "tuning" the antenna? You get the picture, I KNOW NOTHINK!:D

Mudderoy
07-01-2009, 07:03 PM
Your radio coaxial cable and antenna much have matched impedance. 50 ohm radio, 50 ohm coax and 50 ohm antenna.

Your best radiation patten is going to be from an antenna mounted in the center of your roof. This may not be practical. Putting it anywhere is will change the radiation pattern. Most people put the antenna on the passenger side rear. This "points" the strongest signal in the direction of the most metal on the vehicle. This means it would be "pointed" to wards on coming traffic. This is good if you want to talk to people traveling in the opposite direction that you are going. You know "smokey" reports?

Many radios come with a SWR (Standing Wave Ratio) meter built in. If your CB has this then the only thing else you'll need is a way to cut the stainless stinger down and a allen wrench to move the stinger up and down.

If not you'll need to buy, or borrow a SWR meter. The SWR meter measures the amount of power out to the amount of REFLECTED power back into your radio when transmitting. Having a low SWR means that the majority of the radio frequency energy (Power in watts) is going to the antenna and not coming back to the radio.

This reflected power causes the final transistors in your CB to heat up, and eventually causing them to fail.

To adjust the SWR on your CB you go to channel 1 and take a SWR reading. Refer to your SWR meter on how to calibrate and measure your SWR.

Now go to channel 40 and measure your SWR. If the SWR is higher on channel 1 than 40 your antenna must be made longer. If the SWR is higher on 40 than 1 your antenna must be shorter.

When you are doing these measurement make sure you are in the Jeep with the doors closed. You should be away from trees and other vehicles. You, the doors, the tree that is 5 feet away from your antenna, or your wife's car are all potential reflectors. That mean that the energy coming off your antenna will be reflected back to your radio. This will give you a false SWR reading.

Make your adjustments in increments of an 1/8 of an inch. If you've moved it around as much as possible and you cannot make the antenna short enough, it's time to cut. Cut the bottom of the stainless steel stinger. Do not remove more than 1/8 of an inch at a time. You can't put it back on once you've cut it! :D

Each time before you make a measurement, snug down the allen screw so it makes good electrical contact.

The simplest antenna to use is a 5/8 wave magnetic mount. You can put this on the roof of your Jeep and take it off when you are not using it. Just run the coax in the crack of the door.

If it hits something on the trail it just falls over, no biggy. If you need a major mag mount let me know and I'll point you to a 3 or 4 magnet mount setup that I doubt would come off if you rolled the Jeep!

I think that covers the basic stuff. I would tune the SWR for channel 20, or 19. This means no matter which way you go in the channels your SWR will be even across the CB band.

I know we have at least one other HAM on here, and I'm sure several people with CB experience. So if I missed something, or said something wrong please feel free to jump in and add to or correct.

BlueXJ
07-01-2009, 07:58 PM
Can you give us a link to that magnetic mount you spoke of Muddy??

Voldemort
07-01-2009, 08:00 PM
Dude I always go to a local guy that offroads with use add he has all the stuff and hooks them up for me.

firehawk
07-01-2009, 08:20 PM
Appreciate all the input here. I haven't bought a CB yet, but when I get a chance to go wheeling with the Michiana Jeep Club I figure I should have one.

xjjeepthing
07-01-2009, 08:21 PM
Mud pretty much covered it. Idealy the antenna should be 2 foot above the vehicle.
http://www.firestik.com/Tech_Docs.htm

firehawk
07-01-2009, 08:29 PM
Mud pretty much covered it. Idealy the antenna should be 2 foot above the vehicle.
http://www.firestik.com/Tech_Docs.htm

Where did you get your antenna mount? I know I've seen them somewhere, but can't remember where.

Your buddy at Motion Offroad sells them, but their out of stock right now.:headbag:

Sorry....that was just wrong. I'm sorry.:sign0181:

xjjeepthing
07-01-2009, 09:34 PM
I bought mine from a guy that made them on NAXJA, as far as Motion :moon::fyou::bsflag::smiley-stargate014:. I know where Id like to stick that white flag.

Mudderoy
07-01-2009, 10:28 PM
Can you give us a link to that magnetic mount you spoke of Muddy??

The last CB antenna I had on my Blue 4x4 in the early 80's. It was a K40. They still sell them and you can get it with a mag mount.

This is the first place that I found it, seems pricey.

:link: (http://www.rightchannelradios.com/k40-cb-antenna-108/k40-cb-antenna-58-magnet-mount-483.html)

My brother in-law that has done the CB thing more recently liked the Wilson antenna.

I see a lot of the 4 foot fiberglass whips mount on the back of the XJ's. You can rig a mount that bolts in behind the left or right tail lights. You can also run the coax through there as well, but like I said it this mounting spot makes the antenna transmit and receive pattern more directional.

BTW, it's not super direction, it just favors the direction of the most metal. You will get better reports more often with an antenna who's radiation pattern is omni directional.

Melissa
07-02-2009, 12:51 AM
Where did you get your antenna mount? I know I've seen them somewhere, but can't remember where.

Your buddy at Motion Offroad sells them, but their out of stock right now.:headbag:

Sorry....that was just wrong. I'm sorry.:sign0181:





I bought mine from a guy that made them on NAXJA, as far as Motion :moon::fyou::bsflag::smiley-stargate014:. I know where Id like to stick that white flag.


I assume that jeepthing is sooooo not a fan of this Motion Offraod guy !?!?!

Nosey Mel would like some input :D

firehawk
07-02-2009, 11:42 AM
It's a long story.....:rolleyes: I'll leave it to xjjeepthing to explain...if he chooses to.:popcorn:

Mudderoy
07-02-2009, 12:41 PM
It's a long story.....:rolleyes: I'll leave it to xjjeepthing to explain...if he chooses to.:popcorn:

Oh he has too now. Sounds like a funny story all ready.

firehawk
07-02-2009, 02:54 PM
Oh he has too now. Sounds like a funny story all ready.


:headshake:No it's not a funny story at all!:headshake: I raz him about it ever so often, but what happened is NOT funny. The more I've learned about it from him, and seen for myself, it's understandable how he feels.

BlueXJ
07-02-2009, 03:08 PM
The last CB antenna I had on my Blue 4x4 in the early 80's. It was a K40. They still sell them and you can get it with a mag mount.

This is the first place that I found it, seems pricey.

:link: (http://www.rightchannelradios.com/k40-cb-antenna-108/k40-cb-antenna-58-magnet-mount-483.html)

My brother in-law that has done the CB thing more recently liked the Wilson antenna.

I see a lot of the 4 foot fiberglass whips mount on the back of the XJ's. You can rig a mount that bolts in behind the left or right tail lights. You can also run the coax through there as well, but like I said it this mounting spot makes the antenna transmit and receive pattern more directional.

BTW, it's not super direction, it just favors the direction of the most metal. You will get better reports more often with an antenna who's radiation pattern is omni directional.


K40 magnet mount is what I currently have but thought there might be a better antenna nowadays. Thanks Muddy!!

xjjeepthing
07-02-2009, 07:04 PM
My antenna is a 4 foot Wilson. Works great. Have it tuned very well and I can talk for quit a long distance with it.
Kim use this mount in the rear hatch http://www.walcottcb.com/firestik-ss204a-adjustable-ss-vertical-door-jamb-mount-p-317.html?cPath=28_353_430

This antenna
http://www.walcottcb.com/wilson-fgt-silverload-fiberglass-antenna-p-914.html?cPath=28_352_412

This Coax
http://www.walcottcb.com/18-belden-clear-coax-cable-18s8xc29-p-209.html?cPath=28_355_437

This stud mount
http://www.walcottcb.com/stud-mount-jbc930-oversize-p-251.html?cPath=28_354

And if you want to be able to take the Antenna off
http://www.walcottcb.com/kdt-twist-quick-disconnect-p-263.html?cPath=28_354_446

As for the CB I have 2 a Midland and a Cobra. I love the cobra but its alot bigger and takes up more room
Midland
http://www.walcottcb.com/midland-1001z-miniature-mobile-cb-radio-p-735.html?cPath=340_377_379
Cobra
http://www.walcottcb.com/cobra-18wxstii-cb-radio-with-weather-radio-p-518.html?cPath=340_377_379


Now as far as Motion Offroad. I really not sure an open forum is a good place to explain.
Its a fairly long story, Adam is the guys name that Owns Motion as well as A group called Great Lakes XJ. Lets just say if I ever get the chance to break his nose I will. Our paths will cross again, he is less then 100 miles from me.

lowrider
07-05-2009, 02:52 PM
Firehawk to bad you don't live closer I have a swr meter I got from my dad. I still haven't found a good place to mount mine in the jeep yet

JG-Man
08-22-2009, 03:01 PM
I am selling 2 Midland CB radios I have them posted in this site's Classified and on NJ/NYC Craig's List. I am selling them cheap so offering them to XJ Talk members outside of the local area as well.

:link: (http://www.xjtalk.com/classifieds.php?do=showad&adid=8&title=midland-40-channel-cbs)