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Discussion Starter #1
I've been doing a lot of reading on this forum and others about the best way to install a CB and antenna. To say there's a lot of conflicting information would be an understatement. However, I believe I've come up with a decent plan based on the things most members seem to agree on. I think I've about ironed out my parts list and install method but wanted to double check with the other, more experienced forum members before ordering anything.

PARTS LIST
Mount: LoD Destroyer Antenna Mount
Antenna: Firestik FS2-B Antenna
Stud: Firestik K4A Stud Mount
Coax: Wilson 305-830 RG-8X Coax w/ Boot and PL259/FME Connectors
Radio: Either a Uniden CMX760 or a President Johnny III.


I plan to cut the power leads at the back of the radio and install a quick disconnect. The power leads will be wired directly to a 20 amp relay on an Apollointech relay control module under the hood. I will replace the 20 amp fuse the relay control box comes with for that circuit with a 3 or 5 amp fuse to protect the radio. I'll run the RG-8X down the passengers side of the tub and to the rear tail gate. I will sand away the powder coating on the antenna bracket where the antenna stud meets it, and where the mounting bolts bind it to the tail gate. I feel this should give me a reasonable ground plane without requiring a hood mount. If necessary I'm considering mounting a grounding strap from the tail gates gate side hinge bolts to the tub side hinge bolts to ensure a proper ground. I'm aware I'm running a rather short antenna but anything taller will get hit by my rather low garage door.

Any thoughts? Am I miss anything?
 

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RG 8x is a waste of your money. RG 58 is all you need and you, nor anyone else, can show ANY difference in performance in your application.

I assume you want a relay so that the radio shuts off when the Jeep shuts off? That is ok, but if you want to listen while parked on the trail it is less convenient than just direct wiring the CB with your fuses and disconnect. Sure, you have to turn it off manually, but even if left on the power draw is slight.

An antenna that short is a very large compromise. Don't expect performance to be great with it. But, it will work when close to others.
 

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RG-58 not RG-59. 59 is 75 ohm, 58 is 50.
Otherwise, agree 8X is not needed, can't hurt, but won't help.
Look at the bottom of your stud mount link. There is a suggested 58 cable that's half the price.
 

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note on the Wilson RG-8 w/FME, on my JK it had a higher SWR reading than my aries CB cable. On the Aries I was able to get 1.5 SWR across the band,on Wilson the best was 2.1.
 

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Discussion Starter #5
RG-58 not RG-59. 59 is 75 ohm, 58 is 50.
Otherwise, agree 8X is not needed, can't hurt, but won't help.
Look at the bottom of your stud mount link. There is a suggested 58 cable that's half the price.
Cost, while a factor, wasn't my primary concern. My primary concern was being in a potentially electrically noisy environment as well as potential wire fatigue due to the opening and closing of the tail gate. If you all truly believe that the heavier gauge wire isn't necessary for my power levels then I can absolutely drop down to RG-58.

As far as antenna length I'm now considering carrying a 4' antenna under my back seats and putting in a quick disconnect. That way on trail days I can swap out to the taller antenna, and keep the shorter one for commutes around town.
 

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RG-58 not RG-59. 59 is 75 ohm, 58 is 50.
Otherwise, agree 8X is not needed, can't hurt, but won't help.
Look at the bottom of your stud mount link. There is a suggested 58 cable that's half the price.

Correct! Glad you caught that, I fixed my post. RG-59 is for cable tv! Brain Fart!
 

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Cost, while a factor, wasn't my primary concern. My primary concern was being in a potentially electrically noisy environment as well as potential wire fatigue due to the opening and closing of the tail gate. If you all truly believe that the heavier gauge wire isn't necessary for my power levels then I can absolutely drop down to RG-58.

As far as antenna length I'm now considering carrying a 4' antenna under my back seats and putting in a quick disconnect. That way on trail days I can swap out to the taller antenna, and keep the shorter one for commutes around town.
I suspect the RG-58 would be less susceptible to wire fatigue. RG-8 cable is MUCH larger diameter and not nearly as flexible. No real difference in noise. The only advantage RG-8 has is less loss of signal, but really only on VHF and higher bands. CB frequency, especially for the length used in a vehicle simply won't care if it is RG-58 or RG-8. Now if you want to run 2,000 watts, that is different.....

Try the smaller antenna and see if it works well enough for you. I am running a 48" Firestick bumper mount and it is just above the roof. I also have a 108" whip I run there. Shorter antenna is a lot easier to live with......
 

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Skipp, use the 58 it will work fine.

Real, I just assumed you hit the wrong key :)
 

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Discussion Starter #9
I suspect the RG-58 would be less susceptible to wire fatigue. RG-8 cable is MUCH larger diameter and not nearly as flexible. No real difference in noise. The only advantage RG-8 has is less loss of signal, but really only on VHF and higher bands. CB frequency, especially for the length used in a vehicle simply won't care if it is RG-58 or RG-8. Now if you want to run 2,000 watts, that is different.....

Try the smaller antenna and see if it works well enough for you. I am running a 48" Firestick bumper mount and it is just above the roof. I also have a 108" whip I run there. Shorter antenna is a lot easier to live with......
What quick disconnect are you running and has it had any impact on your SWR?

Thanks guys for the input. I know this topic has been done to death.
 

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install pdf - this may help you

Skippman,
attached is my install and includes all the items purchased. Only thing missing was the Antenna calibration. Different CB unit but the install is similar to what you want.
hope it helps.

No worries asking questions... ask away

ps: note that on the cable coming from the tailgate, I initially tapped it down a bit to tight to the door strap and over a period of 2 yrs the cable pinched and shorted. So my new cable is covered in cable loom and not tied down as tight.
 

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dup.. the file is to big, PM me if you want and I can send it to you.
 

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What quick disconnect are you running and has it had any impact on your SWR?.
You don't need a quick disconnect for the antenna with the Firestick FS-2B, it's short enough that it will never snag a garage door or roof. Plus a quick disconnect makes an antenna both physically longer and electrically longer which can make it harder to get tuned to a good low SWR.

Agreed on using standard RG-58 coax cable. There's absolutely zero benefit to running the larger diameter RG-8x for a CB installation inside a Jeep.
 

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What quick disconnect are you running and has it had any impact on your SWR?

Not running a quick disconnect on this rig. Just screw the antenna into the base. Not much more work than a quick disconnect. Quick disconnects have advantages, but they can also cause issues. If you get your antennas SWR set correctly, swapping them out on the same quick disconnect won't change SWR. The added length will effect SWR, but many times the adjustment afforded by the adjustable tip on the Wilson antenna will match it up just fine. Once set, it will stay there.
 

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What quick disconnect are you running and has it had any impact on your SWR?
If you decide to use a quick disconnect be sure to use a good one. Some of the inexpensive bayonet style disconnects wear quickly with resulting signal degradation and potential/eventual failure of the disconnect itself.

I use Breedlove mini quick disconnects on my CB antennas so that I can quickly change between 2' and 4' antennas. They are all-brass construction and very well made. Unfortunately, Jerry Breedlove is no longer making the "mini" quick disconnects, but he does still offer a quick disconnect stud mount for $30:



See: https://www.breedlovemounts.com/quick-disconnect-coupling.html

Although quick disconnects do indeed lengthen an antenna electrically, and I had one many years ago that made my antenna tough to tune and which eventually fell apart, I have not experienced any issues tuning either my 2' or 4' Firestik antennas to acceptable SWR readings with the Breedlove quick disconnects. I must note, however, that tuning the 2' antenna was more work with the Breedlove quick disconnect and SWR readings are slightly higher than without it, but still under 1.4:1 which in my opinion is good enough for a CB in a jeep.

Some may wonder why I bother with the 4' antenna if performance from the 2' antenna is "good enough". The answer is that sometimes it isn't good enough, fiberglass antennas are relatively cheap, and I wanted to experiment. I do get measurably better Tx/Rx range with the longer antenna and I can get my SWR down to just under 1.2:1 across the band with the Breedlove quick disconnect and probably a bit lower if I spend more time fiddling.

There are occasions when I want that extra range and there are times that overhead clearance is my primary consideration. My Breedlove quick disconnects allow me to switch between antennas in seconds.
 

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Discussion Starter #15
Whoa, those mounts are hardcore! I think I'll probably pick up two of the quick disconnects. I want to have a daily driver antenna (2') that will clear my garage and a 4-5' antenna for mountain and trail days.
 

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If you order, inquire first whether they sell the two pieces for the antenna side separately. Breedlove used to sell an "accessory pack" for the mini quick disconnects for the purpose of setting up a second antenna. However, the last time I ordered those parts were no longer available separately and I had to order two complete units.

Also, pay attention to where you want to locate the antenna mount and how you want to connect to coax. There should be options for ring terminals or SO-239. Many of the Breedlove stud mounts require a 5/8" hole rather than the typical 1/2" for CB stud mounts. I simply enlarged the 1/2" hole in my Teraflex tail light bracket to 5/8".
 
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I don't have much to add other than the reviews on the Uniden say that with the external speaker plugged in, the speaker in the mic is still active.

For that reason, I went in a different direction from it a couple of weeks ago. I needed to retire my BC980 due to size issues with the new roll cage.
 

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@Skippman,

Since you showed some interest in the Breedlove quick disconnects, here are some photos of my CB antenna and mount:







Two Caveats:

(1) This setup is overkill for a CB install. The Firestik K4A stud mount is inexpensive and will handle a 4' antenna. However, I was toying with idea of being able to add a mast in camp for extended reach, perhaps for use as a private 2m repeater, so I decided to use a mount with some beef that would work for whatever radio or antenna I owned or was likely to acquire in the future. Besides, it looks cool and was only $15.

(2) This setup is not intended to be an example of a textbook installation. It purposely violates nearly every rule of antenna installation because I was more interested in balancing competing needs than seeking maximum performance. I also wanted to experiment with how antenna location, height, length, presence or absence of a spring and quick disconnect, etc. actually impacts a a real world CB installation. Ironically, now that I've intentionally done nearly everything wrong I am in the position to be able to report first hand whether it made any difference.

Observations:

Much to my surprise, even when violating nearly all of "the rules,"
this antenna mount with a 2' Firestik antenna is still effective for communicating on the trail in large groups even when the group has started to spread out. However, range is limited to no farther than tha. Tx/Rx range for the 4' Firestik is measurably farther. The bottom line is that performance is adequate for the intended purpose despite the installation's many shortcomings.

Performance may and likely will be improved by addressing the following, which I will get to eventually. Maybe.

Location

The optimum location for mobile antenna performance is dead center in the steel roof of a vehicle, the location which provides the greatest ground plane. We can't do that in a jeep, so the next best place would be the center of the hood and after that the cowl. Above the tail light is far down the list, however it is often the best compromise location all things considered such as impeding visibility, protection from trail hazards, distance from engine electrical noise, etc.

Top of Antenna Below Roofline and Potential Interference from Nearby Metal Surfaces:

One typically wants an antenna as high as possible, preferably completely above the roofline. No part of my 2' antenna extends above the roof yet I can still hear people and they can hear me. Approximately 1/2 of the 4' antenna is above the roof and I am able to transmit farther with it.

In theory, sandwiching an antenna between a hard top and/or roll cage and a steel jerry can will substantially reduce antenna performance. Just imagine all those radio waves bouncing back and forth with the antenna in the middle. Also, CB is line of sight technology and the location I choose is the functional equivalent of the bottom of a well. Also, at that time I had not yet added the jerry can bracket so I didn't even think about a steel jerry can's effect on the antenna. Thank goodness Tx/Rx turned out to still be adequate with the jerry can in place.

Quick Disconnect

As mentioned in another post, these make an antenna electrically longer. 2' antennas are difficult to tune as it is; adding a quick disconnect makes it more difficult. However, it didn't really seem to matter with the Breedlove quick disconnects and even if had mattered my reasons for wanting the disconnects outweighed the disadvantages.

Antenna Spring

One CB retailer uses the phrase "every antenna deserves a spring" and lists several reasons why on its website. However, some jeepers don't like springs because they believe springs aren't necessary for short antennas. Others believe that springs just allow an antenna to bang incessantly on the top or rollcage. I wanted to see what effect a spring really had on tuning, and purposely mounted it underneath the quick disconnect base so that I would only have to buy one. The spring makes the 2' antenna very difficult to tune and it does have a measurable effect on SWR. Also, it isn't necessary as an impact protection device for the 2' antenna because it does not extend above the roof line. However, I also run a 4' antenna which sometimes does come in contact with overhead obstacles so I decided to try a spring. Fortunately I had no difficulty tuning the 4' antenna with spring in place and the SWR readings are low.

My inclination is to ditch the spring because it isn't necessary for the particular antennas I use. I've left it there only because it doesn't seem to be hurting anything and re-tuning the antennas isn't high on my "to do" list.

Flag:

I can't tell you exactly what wrapping a radio antenna with a flag will do to performance, but I can say with certainty that whatever it is won't be an improvement. I needed a way to fly an American flag in a parade and a club flag at an event and the flag sleeve I'm using lets you zip different flags on and off. I haven't had a chance to experiment with it to chart the difference in Tx/Rx distance. I'll take it off if I observe any difference but so fare performance doesn't seem to be affected.

Parts Shown in the Photos:

Teraflex Tail Light Antenna Mount, Breedlove Stud Mount P/N 206, RG58A/U coax with ring terminals, Firestik heavy duty spring, Breedlove mini quick disconnect; Firestik 2' antenna, flag system from foreverwave.com. (Not shown: paint removed from back of Teraflex bracket and jeep body, 1/2" tinned copper braid ground straps from bracket fasteners to body, body to frame, exhaust to frame.)


Moral of the Story:

You don't need to do everything by the book to get decent CB performance.

Get clean power directly from your battery, use quality coax from a reputable source and don't kink it or coil any excess, make sure your antenna mount has a good RF ground, assemble your stud mount correctly, and tune your antenna. That's about it.

Even if you put your antenna in the worst possible position and use all the stuff that radioheads try to avoid like disconnects and springs, you are still likely to be able to hear people and they will be able to hear you - at least over short distances. Fine tune your system from there.

Happy CB shopping.




___________________

Wondering what the heck the bronze prospector in the photos might be? See this thread, particularly Post #31 which is the true story of where the Rubicon Prospector jeep hood ornament originated. http://www.jeepforum.com/forum/f8/gold-miner-hood-ornament-65457/index3.html This one was on a '54 CJ-3B that my dad bought used when I was 12 and has been mounted somewhere on every jeep I have owned since. He sits where he is temporarily until I can relocate him to the front bumper.
 
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Discussion Starter #19
Mr. Bills,

Wow, just wow. Thanks for that. I feel like that info should be stickied somewhere.

I was kicking around, looking at different mounts when I found this: Rugged Ridge 17212.20 mounting kit.

Now I know, I can practically HEAR everyone shouting "multiplexers never work!" Normally, I'm inclined to agree given that most kits advise you to use your existing antenna. This kit completely replaces the mount, the cable, and gives you a standard CB antenna mount. I think I'm going to try it out.

It seems fairly close to a fender mount.
 

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. . . I was kicking around, looking at different mounts when I found this: Rugged Ridge 17212.20 mounting kit.

. . . I think I'm going to try it out. . . .
Don't do it. You might as well light that $120 on fire. Better yet, give the $120 to a charity so it will actually benefit someone.

The reason so many people say that these devices don't work is because they don't.
 
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