Is my CB junk?
Discussion in 'CB Radio Forum' started by dodgeram440rt, Sep 30, 2010.
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No expert here, but what are you using for an antenna?
From what I read, more than the radio, the antenna is the most important thing. You can have $300 radio and if it is hooked up to a lame antenna you have a $300 paperweight. -
Hey Dodgeram440rt, what brand and length of antenna are you using? Have you checked the standing wave ratio (SWR) with an external meter? If so, what is your SWR?
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As stated in my post at the top of page 2, I'm using the stock dual mirror mount antennas on my Freightliner Columbia. I have no idea what swr is or how to check it. Should I care? I've turned the squelch and gain knobs in both directions, doesn't seem to make much difference. Like I've said, this is a pretty cheap radio. Some of you talk about buying a cheap radio and it worked fine, but let's compare the difference. The radio is brand new, it's cheap because that is exactly what it is, a cheap radio. The radios you all bought cheap was an old, used radio that probably cost pretty good when it was new. See the difference?
Also, the comments about maybe the second half of the conversation is out of my range are a good valid arguement. So let me ask y'all this, How many of you have the same problem? If it was a matter of distance, it would seem to me that others would have this same issue.
I really do appreciate everyones advice on this. As I've said, I'm a complete idiot when it comes to radios. I just want to plug it in and be able to talk and hear on it. Is that really too much to ask? I mean, that is what it's supposed to do anyway, right? Why does it have to get into all this fancy stuff like special antennas or peak tuning, or whatever? This is a Midland $30 brand new radio. If it's a garbage radio, just tell me. I won't be offended. It's what I could (can) afford. If it's the best I can get for the money, I will live with it until I can upgrade to a Cobra or something.
Thanks again for the help. -
One thing....a radio that transmits REQUIRES the ANTENNA be tuned. Failure to do so can result in Poor performance, and early failure of the attached radio!!
Before you freak out...it is likely the prior driver had a radio...and hopeful tuned it, so it might be OK. IF you mostly listen...no harm. A high SWR will greatly affect transmission...it will effect you range, and the radio's internals. Bust just listening is OK.
You admit to being an idiot...but don't be so hard on yourself...you are trying to learn, so your pretty smart! We all had to learn how to use a radio somewhere....so don't be too hard with yourself. Play with the squelch....keep it adjusted to it just barely makes static sounds.....and re-adjust it as needed.
If you hear only HALF a conversation, just adjust the gain upwards some...the second half of the conversation might become available...and readjust the squelch again.
If the the squelch is turn to make it to insensitive, meaning to far from where it makes noise, you will loose any transmission that is not very strong....too sensitive, and you will hear lots of static and background noise between conversations.
Remember...more gains helps you listen to weak signals, and the squelch should usually be set to just barely make noise....you must determine the best amount of each to run...these radio's are ancient technology, and require some fiddling, and playing with to make work...after a while, it will be second nature. They are NOT PLUG AND PLAY like modern electronics. -
Sounds like either the antenna or the cable to me.
I would buy my own and run it. Also on some company spec'd Volvo trucks and others the antenna wire will run to a communications module. This can get blown at times.
And on some of those trucks they came with 2 antenna's. One is for your FM radio and TV, the other is for the CB.
Just run your own stuff and it will probably solve your problem. -
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The first thing you should do after installing your radio is to find out what the standing wave ratio (SWR) is on an external meter. You really need to care what the SWR is because it will identify whether it is safe to operate your radio without damage to the radio.
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If the SWR is 3.0 or higher, you have a connection problem. And no amount of antenna tuning will change it. Continued use of the radio can and will damage the power transistors and turn your radio into junk that will not be able to transmit a half mile if that far. Fixing the power transistors is expensive and it is usually cheaper to just replace the radio. Checking your SWR is cheap insurance to avoid expensive repairs.
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So if your SWR is 3.0 or higher, the problem is most often a ground plane problem, fault antenna or bad coaxial cable. In simple terms, to much of the signal you are attempting to transmit is being reflected back to the radio and it is raising [bleep] with the power transistors.
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I suspect your problem is a ground plane that is insufficient. If you have access to a mulimeter (volt / ohm meter), on the lowest scale check the resistance between the antenna mount and the chassis ground not the door itself. This reading should be zero. The reading between the antenna mount and the door may be zero but because paint is an insulator, the door can be isolated from the rest of the truck. Thus, your ground plane is not large enough. If you install a ground strap from the door to the door frame that has good metal to metal contact, I suspect your problem will be fixed.
The easy way to troubleshoot an excessively high SWR is to replace the antenna with a known good antenna and recheck your SWR. If necessary, temporarily replace the coax from the antenna to the radio with a known good coaxial cable and recheck the SWR. If neither replacing the antenna or coax lowers the SWR below 3.0 then, by process of elimination, it must be a ground plane problem.
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Most CB radio problems are not the result of the radio. The radio, expensive or not, does not make all that much difference in transmit range. The antenna is most important to getting out. The coax is a distance second when it comes to range. Most problems are the result of antenna, coax, mike and/or faulty installation.Last edited: Oct 3, 2010
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