CB radio

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  #11  
Old 07-29-2008, 02:52 AM
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Just checking :P
 
  #12  
Old 07-29-2008, 04:17 AM
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I have a Cobra 29 Classic with 4 foot Firestick antenna. I went all out on a coax, got a thick 18 footer. I calibrated the SWR myself. They sell the calibrator at truckstops for $10-$15 bucks. You want the SWR to be less than 2, mine is at 1.

I'm not sure how far it gets out. Everytime I do a radio check I get a response saying it sounds good. It gets a nice, clear reception.
 
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  #13  
Old 07-29-2008, 05:10 AM
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Originally Posted by Colts Fan
I have a Cobra 29 Classic with 4 foot Firestick antenna. I went all out on a coax, got a thick 18 footer. I calibrated the SWR myself. They sell the calibrator at truckstops for $10-$15 bucks. You want the SWR to be less than 2, mine is at 1.

I'm not sure how far it gets out. Everytime I do a radio check I get a response saying it sounds good. It gets a nice, clear reception.
I got the 18' clear cover coax cable. Mine is at 1 as well! I angled my antenna straight forward and my swr was high like 2-3 and I angled it forward and it went down to 1. :?
 
  #14  
Old 07-29-2008, 09:47 PM
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SWR Calibration is not a device to tune your radio with a knob, to whatever the conditions are!

The SWR feature on radios is to allow the user to see if the antenna is in tune with the radio! A physical adjustment to the antenna length and or placement and grounding needs to be done to adjust SWR!

The only other method is to use a matching device, which to my knowledge has not been built into any factor Cobra, Uniden, Galaxy, etc!

Go to this site for an excellent primer on antennas and tuning! http://www.firestik.com/Tech_Docs.htm

Originally Posted by WarHorse
I strongly recommend getting a model with SWR calibration. (Most Cobras and more expensive brands have it.) You can tune your radio as needed according to weather and whatever else effects your transmission.

My first radio burned itself out because I couldn't sync the transmitter with the antenna.
 
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  #15  
Old 07-29-2008, 10:01 PM
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Originally Posted by countryhorseman
SWR Calibration is not a device to tune your radio with a knob, to whatever the conditions are!

The SWR feature on radios is to allow the user to see if the antenna is in tune with the radio! A physical adjustment to the antenna length and or placement and grounding needs to be done to adjust SWR!

The only other method is to use a matching device, which to my knowledge has not been built into any factor Cobra, Uniden, Galaxy, etc!

Go to this site for an excellent primer on antennas and tuning! http://www.firestik.com/Tech_Docs.htm

Originally Posted by WarHorse
I strongly recommend getting a model with SWR calibration. (Most Cobras and more expensive brands have it.) You can tune your radio as needed according to weather and whatever else effects your transmission.

My first radio burned itself out because I couldn't sync the transmitter with the antenna.
Horseman is correct. Also let me add that the don't trust the swr when using the one on the radio, get a real swr meter. It's a more acurate reading in my opinion. Also when checking your swr do it in open space away from buildings and cars cause that'll make it run high. Also if the swr is high place your hand on the antenna and move your hand down, if the swr goes down then you need to ground the antenna. Also like Horseman said you may need to adjust the whip only 1/4" at a time though. That can make a difference in the swr big time! Also when checking the swr close the doors!
 
  #16  
Old 07-30-2008, 01:53 AM
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I second the Cobra 25 or 29. I have used a Cobra 25 for more years than I care to remember. Had it tuned and peaked recently just to make sure it was staying on frequency. Found out it was a little off.

Concentrate your efforts on the coax, antenna, and mic. Most OEM installed coax is crap. The coax and antennas need to be tuned to get the best results. A high quality noise cancelling mic is called for.

You would be surprised how well a "cheap" radio can sound when using good quality coax, antennas, and mic. My little unmodified, out of the box Cobra 25 sounds as good or better than most of the so-called "big" radios out there. I can receive a lot of traffic out to 8-10 miles and can reach out clearly that far too. A lot of days, I can pick up skips of radio traffic from around the nation. I have far more invested in the coax, antennas, and mic than in the radio. I run a single antenna, but nothing wrong with duals.

Any HAM operator will tell you... it's the antenna and coax, stupid.

You can get a high dollar radio with all the bells and whistles you could ever need, but if it is shackled to a lousy OEM coax and cheesy antenna, it will mean nothing.

Stick with a moderate radio and get some good coax, antennas, and noise cancelling mic... tune the set up and help the radio reach its true potential. You will be far happier with the money you shell out.

Experiment and have fun!
 
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  #17  
Old 07-30-2008, 09:05 PM
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Cobra and Uniden are both quality radios. The Uniden 68XL is the equivalent of the Cobra 25. The Uniden PC 78XL is the equivalent of the Cobra 29. All four are very good choices. The Unidens tend to be a few dollars less expensive then Cobras.
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The last place to purchase your CB is a truckstop unless there is a sizable rebate or a really big sale. Instead of a regular price truckstop CB, check out Walmart or Target.
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The Cobra 19 is a compact CB radio and Uniden has a competing model the Pro 510XL. These are both basic radios without frills. Good quality CB at an entry level price.
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NOTE: avoid like the plague a Cobra 18. Arguablly one of the worst CB radio ever made if not THE worst CB radio ever produced.
 
  #18  
Old 07-30-2008, 09:20 PM
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Originally Posted by countryhorseman
SWR Calibration is not a device to tune your radio with a knob...
Exactly. The calibration knob does nothing to tune SWR. It is for calibrating the built in SWR meter in the same way you calibrate an external SWR meter. You can only fix high SWR by finding the physical source of the problem, ie. tuning the antennae, proper grounding etc.
 
  #19  
Old 07-31-2008, 01:15 AM
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Originally Posted by Snowman7
Originally Posted by countryhorseman
SWR Calibration is not a device to tune your radio with a knob...
Exactly. The calibration knob does nothing to tune SWR. It is for calibrating the built in SWR meter in the same way you calibrate an external SWR meter. You can only fix high SWR by finding the physical source of the problem, ie. tuning the antennae, proper grounding etc.
SWR?
 
  #20  
Old 07-31-2008, 01:19 AM
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Standing Wave Ratio
 



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