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CB radio antenna

6.6K views 38 replies 15 participants last post by  Siegfried98  
#1 ·
It seems like two common options are 102" SS whips and 48" fiber glass. The 102" seems a bit long and from what my research has yielded, with a good setup a 48" can be pretty good. So the question is, why go with a 102"? Is there something I'm missing? It just seems too impractical.
 
#2 ·
Well, it is about priorities. If you are looking for the best, the 102 is usually the best. I say usually because other factors come into play, often that other factor is mounting location. But if other factors are kept the same, the 102 is best.
On an SUV, I will usually go with a 4 foot fiberglass antenna mounted on the fender. The 102 just seems too tall for my tastes to be mounted in that spot, and if I mounted the 102 on the bumper too much signal would be blocked by the body of the SUV suit me.
So, it really is a compromise and deciding what your own priorities are will decide your setup. But please remember that the antenna and feedline are the two most important parts of your system, don't skimp on them. A good antenna and feedline hooked to an ok cb will outperform a good cb hooked to and antenna and feeling that is only ok. Do the best you can with what you got.
 
#3 ·
Some wheeling events have banned the long whip antennas, as people have been hurt by the antenna whipping around when hit by tree branches and such.
 
#4 ·
#6 ·
It's not optimal according to the experts, but I had the antenna on the door of the RS for years and never had a problem communicating with trail rides. That's not long range use though.

It was a great place to avoid tree branches and such:

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After looking at the options, I probably will use the same setup for the LS. I had the magnetic mount antenna that came with the LS on the trail run at Gilbert a couple of weeks ago, and the antenna was constantly in jeopardy from tree branches, and even got knocked off the roof once. Not gonna do that again.
 
#7 ·
With all things equal, the biggest factor will be geography. Out west in the wide open spaces, almost anything will work, etc.
 
#8 ·
Boy that's a long winded link, though accurate.

The short of it is this, 102"ss+ heavy duty 6"ss pot belly spring = 1/4 wave length antenna. {108"}
(this is the longest & the best feasible performer for mobile use)

Shorter antennas have the same 108" of wire, just in a shorter package.
(either coiled up & molded into a fiberglass rod, or wrapped around the rod & covered in shrink tube)

Most people can't handle the whip, it's tall, if people are dumb enough to be within 9' of a truck on a trask while it's moving they may get reality checked.

I always say NEVER mount below your fender top, the vehicle body is the ground ing half to your antennas positive side, the more sheet metal you can get below you're antenna the better. Get the longest antenna you can (coiling the wire reduces it's efficiency) & mount it as high as your daily driving will allow. Be mindful of underpass clearance signs, parking garages, drive through clearances. If you can mount a 102ss+spring on your roof, do it. If you have a 10'-12' "ceiling" get a 5' fiberglass+6"spring & mount it on your fender.

~psguardian

Guess I'm long winded too lol
 
#9 ·
A quarter wave is a quarter wave. Mounting position, quality of the cable and antenna, and tuning are the most important. My 2 foot antenna mounted on my roof rack works just great. I can get a few miles which is fine for CB and more then enough for trail use.

I had a magnetic mount on the roof of mine for a while. It quickly went away though. Getting knocked over by tree branches constantly gets old really quick.
 
#11 ·
Med!c said:
i will probably get a 102" SS + 6" spring and mount it on the rear door. :D RC car style.
That is what I'm planning on, with a 2m antenna off the front... Maybe roof mount maybe fender mount.

~psguardian
 
#12 ·
I have a SS whip mounted on the rear door spare tire mount. I would suggest getting a good quality mount, not a cheap Radio Shack one. I have lost one antennae and almost the second because of a poor quality mount.
 
#13 ·
bellavesus said:
I have a SS whip mounted on the rear door spare tire mount. I would suggest getting a good quality mount, not a cheap Radio Shack one. I have lost one antennae and almost the second because of a poor quality mount.
+1
When you have that much wind resistance no cheapo mount will do lol.

Have you bonded your doors/cab/frame together with grounding straps? (if you think that whip has a good tx/rx range now, just wait until after you do it)

~psguardian
 
#14 ·
No, but maybe I should! Could you suggest a source for the straps to use?
 
#15 ·
You want tinned copper braid, 1/2"-3/4" wide. Bare metal, self tapping screws, star washers, shortest run that won't hinder door swing. Open door to max, add 1-2". One per door-to-cab, four to six cab-to-frame, could put a couple on the hood too. Make sure the motor-to-cab ground strap is good.

The more "RF Bonded" metal you have below the mount point of the antenna, the better.

~psguardian
 
#16 ·
I've never heard of grounding all the doors before. Are they not grounded through the hinges and latches already?

This is a 4 foot Firestik II (adjustable tip) mounted to the tire carrier. In the first picture, I have it mounted directly to the carrier, but it was angled and would hold itself up against the spare. That was a crappy spare and I wasn't concerned about it. Now I have brand new Treadwrights that are a little bigger and I didn't want the antenna constantly touching the tire. A friend built a mount for me to level the antenna out. It is better now in the second picture. The only thing is that the top of the spring is below the top of the tire, so the antenna can only go so far backwards against the tire. I think I might eventually just mount a hook of some sort to the driver side of the roof, so I can just hook the antenna up against the roof on that side. When I hold it there, it makes the antenna only a little taller than the radio antenna up front. When standing up it is about 8 feet 6 inches.

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#17 ·
The straps are not "needed", but they will help. The hinges & latch hold the door on, but they are moving parts which provide spotty grounding at best. Your RadioFrequency grounding is different then DirectCurrent, DC travels the core of a metal while RF travels the surface. the firestick is the (+) half of your antenna, all the 'RF bonded' vehicular metal is the (-) half. The more bonded metal you have, the less resistance there will be from firestick back to radio, this means you'll get better receive / transmit & lower swr.

~psguardian
 
#18 ·
I might do that for the rear door at least, since that is where the antenna is...where might I find tinned copper braid? Is that something a good hardware store would have, or more of a specialty item?
 
#19 ·
psguardian said:
DC travels the core of a metal while RF travels the surface.
This is the only part I dont agree with. The current actually travels on the surface of the wire, not the core.

where might I find tinned copper braid? Is that something a good hardware store would have, or more of a specialty item?
Should be able to get some ground strap from any parts store, they might have to look it up and order it though. Or, GOOGLE SEARCH
 
#20 ·
LOL, "Google" ya say? Have to try that.
 
#21 ·
#22 ·
Enemigo said:
I've never heard of grounding all the doors before. Are they not grounded through the hinges and latches already?

This is a 4 foot Firestik II (adjustable tip) mounted to the tire carrier. In the first picture, I have it mounted directly to the carrier, but it was angled and would hold itself up against the spare. That was a crappy spare and I wasn't concerned about it. Now I have brand new Treadwrights that are a little bigger and I didn't want the antenna constantly touching the tire. A friend built a mount for me to level the antenna out. It is better now in the second picture. The only thing is that the top of the spring is below the top of the tire, so the antenna can only go so far backwards against the tire. I think I might eventually just mount a hook of some sort to the driver side of the roof, so I can just hook the antenna up against the roof on that side. When I hold it there, it makes the antenna only a little taller than the radio antenna up front. When standing up it is about 8 feet 6 inches.

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do you have close picture of the mount for ur antenna on the spare tire??
 
#23 ·
I'll get some pictures for you. The first picture, I just drilled right through the tire carrier and mounted it directly. The problem with that is that the tire carrier is slanted, so the antenna was slanted toward the back. When I put the tire on, it forced the antenna to stand up straight, and it looked great, but it was directly contacting the tire. The second photo is after he built the mount. It is basically just one half of a semi-truck exhaust coupling, and he torched the "feet" and bent them so that it would level the mount out and the antenna would stand up straight and not be constantly touching the tire.

Again, this location looks pretty cool, but the antenna does NOT lay down horizontal like if you went under a low branch. It only moves back (at the top) about 2 feet. For really low areas, you have to get out and hold it to the side.
 
#24 ·
A great place to mount if you want it on the front but out of the way in my opinion is either on the side of the car just in front of the passenger door and mirror, or I've also seen a friend mount his in a slight angle with his snorkel going up the side of his front window, the snorkel helped hide it, I'm not sure on performance of the antenna in that spot though.
 
#26 ·
Here are some pictures. Right after I took these, I took the bracket off so I could sand and paint it. It is drying now and I want to put it back on asap. On the top of the bracket, the nylon washer is first in line, so I'm not worried about removing any paint. Do I need to remove paint from the bottom of the mount hole so I have metal touching metal?

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