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-   -   CB Radio HELP!! (http://www.wranglerforum.com/f40/cb-radio-help-31073.html)

Bignuke 05-25-2009 12:34 PM

CB Radio HELP!!
 
Hey Guys,
I have the Uniden CB radio, me and my dad tried everything to get it to work. Whenever we try and get it in the green, (the SRW) it never goes in the green, it is always in the red. Also the red light for the ANT (antenna) and RV/LV (something like that) comes on whenever I push the mic button down.:bottom:

Any help will be appreciated. Thanks Alot!

stevens243 05-25-2009 01:05 PM

So, you have a meter hooked between the antenna and the radio and the VISWR is out of spec, correct?

If so, what kind of antenna do you have. I don't know what meter you have but it SOUNDS like your antenna is long (which is normal for a new antenna). To shorten it will depend on what antenna you have. It will have a way to do it by set screw, removing some coils from the top etc. You will do that and check the VISWR until it's correct.

stevens243 05-25-2009 01:07 PM

Here is a procedure:

1. Turn CB off and disconnect the antenna coax cable from the back of it.
2. Connect the end of you antenna coax to the SWR meter where it indicates "antenna"
3. Connect the short coax cable coming from the transmitter position on the SWR meter to the back of the CB.
4. Close the hood and doors on your vehicle.
5. Turn on the CB.
6. Set the CB to Channel 1.
7. Set the SWR meter to the FWD position.
8. Key microphone and turn knob until the SWR meter indicates the "set" position. Un-key microphone.
9. Flip SWR meter to the Reflect position.
10. Key microphone and look at the reading on the SWR meter. The lower the reading, the better. If the meter shows in red DO NOT operate CB. Re-check your connections.
11. Turn CB to channel 40. Follow instructions 7-10 again.
12. Adjusting your antenna (matching the 40 channel bandwidth).
* If the reading on channel 1 is higher than the reading on channel 40, you need to lengthen your antenna. Alternately, if the reading on 40 is higher, your antenna is too long.
* For example, if your reading is 1.3 on channel 1 and 2.1 on channel 40 you need to trim down the tip, turn adjusting ring, or pull out wire a small amount, cut it, and tuck it back against the coil.
* If your reading is 2.7 on channel 1 and 1.5 on channel 40 your antenna is too short. the only solution is to add a spring, raise the antenna, or reposition it.
* If any adjustments are needed, they should be made in small increments. Re-check after each adjustment. Be sure to have all components on the antenna when testing, including the tip if there is one.
13. Re-connect the antenna after adjustment.

ccain 05-25-2009 01:17 PM

That's an awesome write up on the SWR procedure Larry!!! I'm gonna sticky this! :punk:

stevens243 05-25-2009 01:32 PM

Here is another great bunch of info on it:

Setting the SWR of Your Antenna© - Firestik® Antenna Company

Let us know what antenna you have. If it's not in the documentation you can find how to adjust the antenna length to fix this problem.

Bignuke 05-25-2009 04:55 PM

It is a highstick antenna, I already tried making it shorter... I might go take some pictures soon to see what it does and possibly a video to show you guys what it does also. I tried almost all of the stuff you listed... I think I need a new antenna...

Thanks! I'll get back to you guys soon.

Bignuke 05-25-2009 04:58 PM

I mean firestick, I'm sorry.

stevens243 05-25-2009 04:58 PM

Before you buy a new antenna is it a grounded antenna? How long is the coax from the radio to the antenna? Is it new coax?

If it's so bad you can't even get it close it's probably the cable to the antenna or the antenna needs to be grounded and isn't (or shouldn't be and is).

Bignuke 05-25-2009 05:04 PM

It is a grounded antenna, I'm not sure what you mean by coax... the radio is in my overhead console and it is going back to the taillight. I cut about 2 inches off of the antenna, might need to cut more??

stevens243 05-25-2009 05:22 PM

"grounded antenna" = you have to ground it to the jeep? With a separate ground wire?

The antenna cable is coax, right?

"cut 2 inches off" means you pulled the end cap off the antenna and unwound some of the copper wire and snipped it off right?

Sounds just like my antenna. I ended up taking 5 or 6 inches off. You should be getting a better SWR reading after taking 2" off.

Bignuke 05-25-2009 06:31 PM

Yes I got a little better SWR reading after 2" but not much at all. Should I keep trying to cut more off?

stevens243 05-25-2009 09:11 PM

Yes, take another 2" off and check again.

crashedking 05-26-2009 09:54 PM

Coax
 
Did you check VSWR with the antenna off? Did it change? If not Did you Ohm the center conductor to ground. Did you Ohm The center conductor to center conductor And ground to ground? Maybe its shorted If not. Check the VSWR while keyed reach out and touch the antenna about mid way if it is a top load. What happens. Then touch the antenna at the base while keyed and observing the VSWR does it get better?

Bignuke 05-27-2009 11:12 AM

What if when I touch the base of the antenna and it gets better? what does that mean??

stevens243 05-27-2009 12:32 PM

It probably means you have a bad ground. How is your antenna mounted?

I don't have any pics available right now, but mine is mounted over my drivers rear tail light and uses the coax connection to the antenna for it's ground.

And define "better". I'm sure you mean that the SWR meter shows closer to green. What meter are you using? Also, check the ohms across the coax using a meter to see if it's grounded.

Bignuke 05-27-2009 01:34 PM

I'm going to go take some pictures for you guys real quick.

Bignuke 05-27-2009 01:47 PM

5 Attachment(s)
The first picture is the kind of CB i got. UNIDEN looks nice.
Second picture is with me holding down the mic button and as you see the ANT light is on and the other one.
3rd is my antenna bracket...

Anymore information would help.
THanks!

stevens243 05-27-2009 02:10 PM

I don't know what the "antenna light" actually indicates on that radio.

Where is the SWR meter and are you hooking it up to the radio or to the antenna?

If that "meter" on the radio doubles as the SWR meter (it looks like it may, but I'm not sure) and that is where it is after taking 2" of wire off the antenna, did you try taking another 2" off?

Firestik sells their antenna's "long". You will want to keep taking wire off, putting the cap back on and trying again.

Also, do it outside, not in the garage (if you are) as you are actually checking reflection and don't want any interference messing with your settings.

Bignuke 05-27-2009 02:13 PM

Yes I took another 2" off but I DID do it in the garage. It raining outside right now so I will try sometime soon. Thanks! If that doesn't help I might look up in the phone book to see if there is a CB Radio place around me. lol

stevens243 05-27-2009 02:24 PM

Ok. What does the antenna light mean?

Also, how much lower did the SWR come down when you removed the 2nd 2 inches?

And I can't tell by the photos but is that white nylon washer in the right place? The antenna is grounded by the coax and that nylon washer is there to keep the antenna from contacting the "ground" on the mount. I can't remember if mine is like that or on the bottom. Actually, mine isn't a washer as much as a seat for the connection. I'm not sure this makes sense to you...

Bignuke 05-27-2009 03:02 PM

Yes it does. I'm not sure where that washer goes... I took the washer off and the SWR got much better when I went into the driveway but when I had it on, it was the same thing as before...

stevens243 05-27-2009 03:28 PM

Ok, bear with me here. I'm trying to help and learn at the same time...

What is that antenna light for?

When you removed the washer, did the SWR come down into the green?

Do you have a multimeter available?

Bignuke 05-27-2009 03:31 PM

I think the antenna light means that it is not getting to the antenna...? (no signal maybe?)

Yes when i removed the washer it went down in the green (to the 3 on the SWR)

And yes I do.

stevens243 05-27-2009 03:38 PM

Progress. How is the radio wired in the Jeep? Hot to _______ ground to_________

Do you have the instructions on the radio? Does is tell you what that light is for? (sorry, it's bugging me that it even has a light)

And don't forget:
1. Remember to check for continuity, shorts and opens in your coax and mount installation first.
2. Take measurements in an open area with the vehicle's doors and hatches closed.
3. All measurements should be taken with antenna tip on, unless you do not plan to use the tip in normal use.

crashedking 05-27-2009 11:09 PM

The light tells him that there is reflected power. This only works for a generic VSWR meter and if the radio has not been tweaked, it will be reliable. The light never turns green. The nylon washers separate the center conductor to the ground. You must have no connection from the center conductor to the ground. This type of antenna does not have a capacitor, and should read no continuity center to ground on the radio connector. Your Antenna selection is not the best for this application. Because behind your soft top is your role bar, it runs parallel with the top load antenna. You will never achieve the best match because when you drive and the antenna moves it will radiate to your ground. The role bar and the power being radiated will cause high reflected power, the red light. This does not mean that this antenna will not work there. I cant tell what type of fitting you have from the pict. (The lower fitting). Leave the antenna connected to the bracket, disconnect the PL259 connector from the radio, take a OHM meter, what does it read across the center conductor to the barrel ground? Hopefully no beep or continuity. Nice bracket and CB. Who installed the PL259 connector on the radio side is it crimp or three piece? Your problem can be solved easily. Quit cutting the antenna, you may have ruined it. Start with what I have told you first.

Jerry Bransford 06-27-2009 05:08 PM

1 Attachment(s)
One more note to add when trimming lengths of wire that comes out of the top of Firestik's more basic antennas that do not have the brass tuning tip. Cutting 2" of wire off at a time is too much length to be cut off all at once. Cutting 2" off might mean you went past the point of minimum SWR and you'd never know it. Instead, I'd be cutting more like 1/2" lengths off at the most. The antenna length at which minimum SWR is achieved is fairly critical and it's easy to miss by adjusting its length too much at a time.

One more thing... most cases of high SWR that can't be tuned down as expected are usually a result of the mount having either been misassembled or it not having been grounded well enough to the tub. The mount must have an adequate surface area of bare steel to bare steel connection so that usually means grinding paint off whatever you're mounting it to.

And a misassembled mount usually results from having either left the nylon/plastic insulated shoulder washer off, or not getting it installed and centered properly. The insulated shoulder washer's purpose is to insulate the whip part of the antenna from the mount. If the antenna itself touches the mount, the antenna will be shorted to ground and a very high SWR will be the result.

The below illustration shows a typical antenna mount and how it should be assembled. Take particular care in seeing where and how the insulated shoulder washer is supposed to be installed. :)

SoCal147 09-23-2009 03:27 PM

Happy Customer and Forum Member
 
Bought the Jeep Uniden 510 kit from Right Channel Radio. The only issue was I ordered the wrong antenna mount. After some slight mount modification [cutting and grinding] I attached the antenna mount to one of the stock tire carrier bolt holes. I had great continuity to ground. Installed the rest of the components. The hardest decision to make was were to mount the radio. Drove out to an open space and followed the directions given above. I got 1.8 on channel 1 and 1.6 on channel 40. Good enough for me. The wrench that came with the WIlson antenna would not bite into the set screw anyways. Either way, the radio worked fine from the get go. Thanks for the above info all.

Patrick

SoCal147 09-23-2009 03:42 PM

4 Attachment(s)
some installed pictures.

SoCal147 09-23-2009 03:48 PM

4 Attachment(s)
More Pictures
#1 4' Wilson antenna. Yellow strip at top is the top of the antenna.
#2 Modded Mount with mount tape showing. I did this to protect the paint and to help secure the antenna. It aint going no where.
#3 Another toy
#4 Yet another toy.

I will never grow old. Just watch me. :wavey:

SoCal147 09-23-2009 04:13 PM

Never did here the end result from BigNuke..........?


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