Howdy all just had a couple general questions regarding CB radios.  If this belongs in the ham radio section let me know. I just figured those guys are in their own league.

I'm wanting to pick up and install a CB in my pickup.  Quite frequently I am driving from idaho to eastern montana or from one of those to northern utah.  there's been times I wish I would have had the radio either for entertainment (listening to surrounding trucks etc) or for hearing about the weather.  I've also started getting back into a little 4 wheeling and would like to communicate with the others.

my old 4 runner had a cb already installed so this would be my first install and I was just curious.

#1. Do modern radios and antennas need to be "tuned"?  I can remember when I was younger watching grandpa tune one but that radio and antenna was from the 70s.  Didn't know if new gear was the same.

#2. I don't want a 6' whip on my pickup. I think they look tacky and in all honesty there's times when stick up too high.  I love flyfishing and some of those areas have thick overgrowth.   If I bought a magnetic 3 foot whip would I get OK range?  Can they be taken off the roof and put back on without adjustments?  

#3 how do you run antenna wires?  if I got the magnetic kind I would ideally love to just run the antenna into the back seat and out the little side vent window and onto the roof but I don't km now how well that works.  If I had to run it through the dash board where does a guy find room to get it out of the cab then back to where ever the antenna is mounted?  If I went permanent it would probably be tool box.


Hope my grammar is OK. Cell phone is all I have right now and I tend to get lazy when typing on it.

Jhans

1)  The antenna needs to be trimmed for minimum SWR.  I bet if you threw a Wilson Lil Wil on the middle of your roof, the radio would be happy with it!

2)  I run a 102" whip, plus a spring, for 108".  No tuning required!  The Lil Wil I mention above would do fine in the middle of your roof.  No retuning required unless you move the antenna somewhere radically different on the vehicle.

3)  Just as you say, run 'em in through the door (the gasket will manage), or window.

Modern radios 'fold back' when presented high SWR, and of course, high SWR is undesirable.  By fold back, I mean the radio reduces power to keep from harming itself.  If I were you, I'd get a Cobra 29, some decent quality mag mount, and enjoy.

Ray

Go to Radio shack before they close and look for a thru window Coax connector.  I don’t know the real name.  Normally they are about 8 inches long, white and have a male coax connector on each end but in the middle, they are flat.  You can lower a rear window, carefully fold it around the glass and raise the window
They are also good for running a cable to a DirecTV or Dish antenna without drilling a hole in your house.

Older Cobra 29LTD Classic and Wilson Lil Will here.

Radio has been worked on a bit, but I can get 5 miles pretty regularly, more if conditions are right, and the other guy has decent equipment too.

I ran the coax out the back door and stuck the mag almost dead center of the cab.  The 29 has a built in meter, but, I still use a separate meter just to make sure.

How big of a role does the CB reciever have on range?  I was looking at one of the more compact receivers.  I don't have a lot of mounting space.

I'll have to go look for a through window coax.  My rear window doesn't roll up or down but it is one of the little wing windows that opens about an inch.

CB operates at relatively low frequencies.  As such, the specifics of the installation of the antenna and the vehicle it's mounted on have a pronounced effect on the resonance (aka tuning) of the antenna.  So any CB antenna should be tuned/adjusted for the particular installation.

Something to realize is that the antenna itself is really only half of the antenna.  The ground plane - the vehicle opposite the antenna - is the other half.  There's a lot of variation in that other half from a radio signal perspective.

When dealing with higher frequency radio communications that are common for land mobile radio, amateur radio, wireless phones etc, the vehicle body is vastly larger in terms of radio wavelength so mounting variations have less effect on antenna tuning, to the degree where those effects can usually be ignored.  CB is more difficult because of the radio frequencies it uses.

If they're used in relatively the same place each time you should be fine.  If you move a magnet mount from say a pickup truck roof down to the front of the bed it would likely change.

Due to the low frequency, magnet mounts are less efficient for CB than direct mounts.  The nature of capacitive coupling (which is how magnet mounts work) tends to reduce the electrical size of the ground plane, so the efficiency hit becomes more apparent with smaller vehicles.  If you put a magnet mount in the center of the roof of a full size van, it will work pretty well.  If you stick a magnet mount onto a roll bar on a jeep, the performance loss will be more.

A full quarter wave at CB frequencies is the length of those long whips you see, 9' or so.  Anything less than that, is a "loaded" antenna.  The more loading, the more loss of performance and reduced bandwidth of the antenna.  Different constructions of loading also negatively impact performance.  The ones with whips about 4' long seem to do reasonably well if used in a good installation (that "other half" of the antenna).  When you start to get much shorter than that, performance seems to drop off more noticeably unless used with a very good ground plane.

A good loaded antenna, installed in an optimum location on a vehicle (center roof) will usually outperform a full 1/4 wave whip installed in a poor location (pickup truck bumper or something like that).

A good quality antenna with a spring would not have a problem with most tree limbs or the like.  Get an antenna made by one of the companies that make products for the land mobile radio market that will be a quality product and quality mounting system.  I would suggest sticking with the standard "NMO" style mount and a base loaded antenna.  From past experience one model I would suggest would be the Maxrad MLBDC2700(S)  which is their DC grounded antenna.  My complaint with those is Maxrad's springs are very stiff, to where they are almost useless.  If you're really needing antenna flexibility, Larsen springs are the most flexible. Antenex springs are in-between.

ps, also see
http://www.ar15.com/forums/t_10_22/679368_Do_you_guys_discuss_any_CB_stuff_.html

ar-jedi

I'll throw this out... if you make the power hookup via a cigarette plug, you get a high current circuit in your car, the ground is easy to connect, and you have some portability if you need to change vehicles...it's not very pretty, but my transceiver mount in my Explorer is some industrial Velcro and a couple of cable ties to the ashtray door.... a center roof mount base loaded Hustler antenna with good SWR gives me pretty reliable 3+ mile car to car range... years ago a car transceiver,regulated 12v power supply, and Big Stick 1/2 wave with very good ground on a 30' mast gave me reliable 12mi range to similar setup in coastal Florida

Thanks, I was having 0 luck finding that...

Another option for you is getting something you can just unscrew when you do not need it. I thought getting a CB would be a good idea... I got a 4 foot firestick and have the mount for it permanently mounted on my front fender but I usually just unscrew the antenna and keep it in my vehicle unless I need it.

On another note... I thought it would be cool to have CB and listen to the chatter. Not sure about your area but I got over that idea pretty quick here in Maine. All i ever pick up is yobos running thousands of watts down south that think every channel is the "superbowl"