CB Radio - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > General Jeep Discussions > Communications and Electronics

Join Wrangler Forum Today


Like Tree1Likes
  • 1 Post By realshelby
Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 03-11-2018, 07:08 PM
Thread Starter
  #1
Newb
 
Join Date: Sep 2016
Posts: 6
CB Radio

I just installed a cobra 75wxst radio in my Wrangler I did it according to the instructions as closely as I could. I can understand The Weather Channel's perfectly they come through loud and clear but I can't hear any CB Transmissions any suggestions. It is installed underneath the glove box on the support bracket and SWR are also perfect. Thank you

OrangeCrush51 is offline   Quote
Old 03-11-2018, 07:14 PM
Thread Starter
  #2
Newb
 
Join Date: Sep 2016
Posts: 6
I forgot to mention it is mounted on my Smittybilt spare tire carrier with a 5-foot Firestik antenna. Thanks again

OrangeCrush51 is offline   Quote
Old 03-12-2018, 12:56 AM   #3
Jeeper
 
sassX's Avatar
 
Join Date: Mar 2014
Location: Ft.Collins,CO
Posts: 245
Did you turn your squelch down to static and back up till it was silent?

When I got mine in and setup I went over to the interstate and initiated a radio check call. Got an answer back and I was good to go.
__________________
Current: '17 JKU Rubi Recon Gobi & '99 WJ limited

Previous: '14 JKURX Amp'D Named: Minion "One of many, One of a kind"
See Minion here
sassX is offline   Quote
Sponsored Links
Advertisement
 
Old 03-12-2018, 10:42 AM
Thread Starter
  #4
Newb
 
Join Date: Sep 2016
Posts: 6
Ya know I did do that and I have had CB Radios before. Maybe it just doesn't have the range that I thought it should have I'm going to drive over by Sapp Brothers this morning and see what happens. Thanks much
OrangeCrush51 is offline   Quote
Old 03-12-2018, 11:46 AM   #5
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 48,228
My bet is your antenna mount was either misassembled or it's not receiving an adequate RF ground from that Smittybilt tire carrier. Getting the antenna mount installed properly is the key to making a CB work properly and it's the usual cause of it not working right. Odds are not good that your Smittybilt carrier is adequately grounded, or at least not good that the mount is receiving an adequate RF ground. Note that an RF ground, what your antenna system needs to work properly, is crucial. It is also far more demanding than just a normal ground like would be enough for a tail light etc. A simple continuity or ohmmeter test is not able to test for an RF ground.

Do you know anyone who knows about CB or ham radio antennas who could help you?
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 03-12-2018, 11:47 AM   #6
Jeeper
 
Mr. Bills's Avatar
 
Join Date: Jun 2017
Location: Area Code 530
Posts: 774
Did you tune your antenna with a SWR meter? What were your readings at channels 1, 20 and 40?

Is your antenna mount adequately grounded to the tire carrier and the tire carrier adequately grounded to the body or frame? (The mount should be grounded, not the antenna itself - check to be sure the antenna mount is assembled correctly.)

___________

Note: There is a school of thought that advocates tuning at Channel 20 and calling it a day, the theory being that since Channel 20 is in the middle of the frequency range if the antenna is tuned at that channel it will be as good as can be expected at channels 1 and 40. While that might not be entirely true, its true enough for a CB in a jeep.
__________________
Mr. Bills
Area Code 530
KG6LMV

'06 Jeep "LJ" Rubicon, '46 Bantam T3-C trailer
Past Jeeps: '49 Willys Wagon, '54 CJ-3B, '65 CJ-5,
'83 CJ-7, '97 ZJ
Mr. Bills is offline   Quote
Old 03-13-2018, 04:27 PM
Thread Starter
  #7
Newb
 
Join Date: Sep 2016
Posts: 6
Thanks to all of you who have replied with your help I do appreciate it . I went clear through and rechecked everything made I Went back made sure everything was where it should be ? took the antenna off the tire carrier , took my Dremel to ground , made sure I was on bare metal. I put it all back together like it's supposed to be and it works great. It just doesn't have the range that I hoped it would have but everything is good and I do appreciate you guys . Thanks for all your help maybe I'll see you on the trail one day
OrangeCrush51 is offline   Quote
Old 03-14-2018, 07:52 AM   #8
Jeeper
 
Join Date: Oct 2017
Location: Houston, Texas
Posts: 348
If you are not receiving any signals/conversations it can simply be that there are none around. CB use isn't near what it used to be.

Grounding isn't really a factor in receiving the signals. You can stick a copper wire into the back of the radio and run it outside a few feet and "hear" quite well ( that is all most high end receivers use to "hear" with ).

What normally happens when you cannot hear but you are sure there are signals out there is a short in the cable. A pinched area where the conductor and ground shield are in contact. Could be the same effect if the antenna conductor is shorted to ground.

That should show up as a problem with SWR, but I have seen SWR show ok with a shorted conductor. You state SWR is "perfect"? What is the actual reading? What is it on Channel 1 and on Channel 40? Should be a noticeable variation as you go from one end of the range to the other.
__________________
2017 JKU RECON silver
realshelby is offline   Quote
Old 03-14-2018, 03:25 PM   #9
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 48,228
Quote:
Originally Posted by realshelby View Post
Grounding isn't really a factor in receiving the signals.
It's not but the possibly misassembled antenna mount I mentioned above can definitely prevent any signals from being received. Putting the mount together incorrectly can easily short the antenna to ground which causes both a high SWR and stops it from receiving signals.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 03-15-2018, 06:55 AM   #10
Jeeper
 
Join Date: Oct 2017
Location: Houston, Texas
Posts: 348
Quote:
Originally Posted by Jerry Bransford View Post
It's not but the possibly misassembled antenna mount I mentioned above can definitely prevent any signals from being received. Putting the mount together incorrectly can easily short the antenna to ground which causes both a high SWR and stops it from receiving signals.
There is a very easy test for a shorted cable/mount/antenna.

Simply loosen the coax where it goes into the radio. Pull back the outer threaded ring ( ground ) until it no longer touches the male threaded part of the radios coax connection. The inner post of the coax should still be able to make contact with the inner female part of the radios coax connector. This makes the cable/mount/antenna effectively a long wire antenna. If your signal reception goes up noticeably, that is a sign there is a problem in the system.
__________________
2017 JKU RECON silver
realshelby is offline   Quote
Old 03-15-2018, 01:37 PM   #11
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 48,228
Quote:
Originally Posted by realshelby View Post
There is a very easy test for a shorted cable/mount/antenna.

Simply loosen the coax where it goes into the radio. Pull back the outer threaded ring ( ground ) until it no longer touches the male threaded part of the radios coax connection. The inner post of the coax should still be able to make contact with the inner female part of the radios coax connector. This makes the cable/mount/antenna effectively a long wire antenna. If your signal reception goes up noticeably, that is a sign there is a problem in the system.
That would not help since that would still leave the center conductor shorted to ground (if that is the problem) at the antenna mount. A better way to test for that would be to unscrew and remove the coax cable connector from the other end of the cable at the antenna mount which would remove the possible short from the center conductor.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 03-15-2018, 04:17 PM   #12
Jeeper
 
Join Date: Oct 2017
Location: Houston, Texas
Posts: 348
Quote:
Originally Posted by Jerry Bransford View Post
That would not help since that would still leave the center conductor shorted to ground (if that is the problem) at the antenna mount. A better way to test for that would be to unscrew and remove the coax cable connector from the other end of the cable at the antenna mount which would remove the possible short from the center conductor.

Well, I know it works.

In fact I will go one step further. On RF signal reception you can actually ground your antenna whip to the vehicle and still receive. That simply forms a loop antenna. RF signal reception is different from RF signal generation. Different rules apply and different parts in the radio are there to do very different jobs.

So, I challenge those reading this to find a CB channel with some traffic on it. Turn it up so you can hear it well. Then go out and ground either the tip or base of the antenna. Which forms a "short". Bet your reception doesn't change all that much! Do the same thing while testing SWR, and that is completely different.
__________________
2017 JKU RECON silver
realshelby is offline   Quote
Old 03-15-2018, 07:03 PM   #13
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 48,228
Quote:
Originally Posted by realshelby View Post
Well, I know it works.

In fact I will go one step further. On RF signal reception you can actually ground your antenna whip to the vehicle and still receive. That simply forms a loop antenna. RF signal reception is different from RF signal generation. Different rules apply and different parts in the radio are there to do very different jobs.
I literally have over 50 years of having designed and made antennas, I built my first ham radio and antenna (a 15 meter two element beam) back in the early 60's. With years of military, ham, and commercial VLF/HF/VHF/UHF work behind me. We are just going to have to agree to disagree.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 03-15-2018, 07:20 PM   #14
Jeeper
 
Join Date: Oct 2017
Location: Houston, Texas
Posts: 348
I am surprised you mentioned your credentials.

I posted the challenge to try shorting the antenna and seeing what effect it has on reception. I went out earlier and triple checked that what I said is correct. I used two additional mobile CB antennas to confirm it.

I hope to learn something new every day. Maybe you can too!
Mr. Bills likes this.
__________________
2017 JKU RECON silver
realshelby is offline   Quote
Old 03-16-2018, 12:00 PM
Thread Starter
  #15
Newb
 
Join Date: Sep 2016
Posts: 6
I actually did find out during the course of checking my antenna that I had placed the plastic washer on the wrong side of the mount .On once I fixed that and checked everything out my SWR'S came out in a pretty good range. Channel one is less than 1, Channel 20 just over 1 .and channel 40 is 1.51 . Thank you all for your help I appreciate it. Gary
OrangeCrush51 is offline   Quote
Old 03-16-2018, 12:05 PM   #16
Jeeper
 
Join Date: Jan 2018
Posts: 67
Hoping to get one soon , helpful info here.

Sent from my SM-G955U using Tapatalk
cody_roberts is offline   Quote
Old 03-16-2018, 02:05 PM   #17
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 48,228
Quote:
Originally Posted by realshelby View Post
I am surprised you mentioned your credentials.

I posted the challenge to try shorting the antenna and seeing what effect it has on reception. I went out earlier and triple checked that what I said is correct. I used two additional mobile CB antennas to confirm it. !
Shorting the radio's signal input connection (the center pin of the RF antenna connector) to ground is going to make it impossible for any receiver to receive signals. Period.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 03-16-2018, 03:02 PM   #18
Jeeper
 
Join Date: Oct 2017
Location: Houston, Texas
Posts: 348
So you didn't try it.

I did.

I actually had two magnet mount CB antennas here that I tried this with yesterday. Both received signals well. Then I touched the whip of the antenna to a known ground on the Jeep, as well as touching the outer connector of the coax where it goes into the radio.

If that isn't grounding the antenna, I will listen to why it is not.

Both times signal reception was about the same as not grounded.

I also took a copper wire and ran from the base of the whip antenna ( whip has outer fiberglass covering so I couldn't get to the inner conductor ) to a known ground on the Jeep. Same effect.

Three different antennas, same result. We are talking passive signal reception. Not going through pre amps or looking at transmit readings.

While I don't have the years of experience you state, I was very active in CB radio for years. Then got my Tech Plus ticket in 1996. Within a year I passed all tests to gain an Extra Class FCC Amateur Radio license. Including the 20 wpm Code. So I won't claim to know everything, but I am far from ignorant.

__________________
2017 JKU RECON silver
realshelby is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off






All times are GMT -5. The time now is 11:29 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC