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Discussion Starter #1
Hello, everyone:

I finally got Mein Byk back from the dealer where the CB radio was installed. I was initially going to do it myself, but then work got in the way and my free time dwindled to nothing. I'm glad I had them do it because they did a superb job. The people at Sierra communications were also very kind with tech help. My problem is that although the CB receives transmissions, no one can hear me when I transmit. I press the PTT button and the signal strength meter goes to max, but the person with whom I tested it today (about 1.5 miles away) couldn't hear me. I could hear her, however. I tried the second helmet and the same was true. I wonder if I was simply out of range (doubtful as I could hear her) or if the CB PTT was somehow wired wrong.

On a side note, I'm wondering if I made the costly mistake I was trying to avoid. Instead of getting the BMW com system, I opted for the JM CB2003, which also functions as an intercom and allows for the radio, CD, and eventual GPS to pipe through the headsets. The CB with the BMW antenna was about $950 and I paid $600 for the 8 hour installation. Please be gentle if you decide to laugh at me for being a fool. Otherwise, some encouragement that I didn't spend too much would be welcome.
 

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I think you made a good choice, but 8 hour for install? Did they install a separate PTT button or are you using the one on the unit? I am using the one on the unit & I had to bend the mounting plate just a little to allow the trigger to go down far enough to transmit without hitting the flasher button.
 

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The big qiestion is did they set the SWR of your CB when they installed it? I bet they didn't. This is a critical step to the point that you should not try to transmit before you make this adjustment. Apparently it could damage your transmitter. The best instruction I could find is at www.firestick,com/tech_docs/setting_swr.htm
You will need a SWR meter and a short length of antenna cable or you can insert the meter in line with your antenna. If that doesn't make your CB talk to others you may need to go back to the installer. Hope this helps.
 

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Discussion Starter #4
Doc:

Come to think of it, I attached the antenna today when I picked up the bike because when I took it in, I could find no way to safely transport the uninstalled whip antenna. Since it's made of metal and only mildly flexible, I couldn't bend it in the topcase. When I picked up the bike today, the installer said I would need to come back to "calibrate" the antenna. I wonder if what he meant is what you suggested. BTW, the link you included doesn't open. Thanks for the input. I'll wait to take the bike back in before I use the radio for transmitting. Is it harmful to use it to listen to my group's transmissions? Those come in loud and clear.
 

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No - until you get the antenna checked, using the CB as a receiver (do NOT transmit) will do it no harm at all.

- Bob
 

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Discussion Starter #6
It's interesting that such a critical step in the CB installation is not even mentioned in the owners manual that came with it. In fact, it's not mentioned anywhere in the package. I'll only use it as a receiver until the antenna is checked. It's just a pain to have to go 45 miles to have the darn thing worked on again. I just don't have the luxury of time. If only I knew where to get my hands on an SWR meter (whatever that is) and how to use it...
 

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Discussion Starter #7
Okay, I finally was able to find the document suggested by docwagner. Now I know what SWR is and how it's set using the meter. Problem is, it's not mentioned in the instructions. The equipment came prepared by J&M as a kit and the antenna is BMW. Wouldn't it stand to reason that it all should jive? This is really disappointing.
 

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Joe, if there's a CB shop closer to you, they should be able to adjust your antenna for a low standing wave ratio (SWR). All you need is a place to disconnect the RG-58 antenna feed line and insert the SWR meter - my '02 LTE has such a "break point" in the feed line under the seat, between the antenna and the sting ray.

No such CB shop where I live, but Miami's a big town. How do you say "low SWR" en espanol ??


- Bob
 

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Did you purchase a SWR meter yet? They can be had for about $12. I purchased one at Fry's electronics. Someone you know probably already owns one.
 

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Joe,

Don't feel bad, the choice was fine, I just installed the same CB on my 2005 LT, took me 3 hours and I took my time and it was my first. I am also an Advanced Class Amateur Radio operator and can offer some RF advice.

1 - I doubt the SWR is off enough to matter at 1.5 miles line of sight, if you were not in sight of each other, it could be an issue. Re high SWR from a mistuned antenna, most radios will back off power when experiencing high SWR to avoid damage, and I expect the J&M one does, but not certain. Avoid any lengthy chats on high power until the antenna is checked. A quick hit should be fine, no dialog past a confirmation at full power.

2 - check to ensure the radio was set to high power for your 1.5 mile test, which is only 5 watts, but should do nicely. I run my on low all the time, unless I need more reach, easier on the radio's amplifier section.

3 - double check the receiving end and ensure they can receive. Have them move closer to verify.

If all else fails, hit a local amateur radio store and see if there is a friendly soul out there who will shoot your antenna with an analyser, most will glady do it for free. The way you tune the antenna is to remove the whip from the stud mount with an allen key, and using a small bolt cutter, slow trim off small amounts from the bottom, reinstall, and check it out at each trimming.

I am a bit disappointed in the 8 hour labour rate, not sure how that was justified by a pro who knows how to strip panels. At that price, they should have tuned the antenna.

I tested my BMW antenna with my MFJ antenna analyser and it seemed to be tuned for 28.143Mhz, a bit high for the CB band which is 26.96 to 27.4 Mhz. In any case the SWR at 26.9 was 2.3 and at 27.4 it was 1.6. The lower the better, and unfortunatley to lower the tuned frequency, the whip has to get longer if it is already optimized higher as in my case. Not ideal, but tolerable, I may construct a small tuned circuit to level the SWR at the radio, but the antenna will still be less efficient. I expect your antenna will be the same.

Hope this helps.

Bruce
 

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Thanks for the clarification on the radio stuff. I too installed my own CB and while I did a bunch of other things at the same time I doubt it would take me, an amateur mechanic, 8 hours to do the job.
 

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Simple idea that may have been overlooked...

Howdy NeoDoc,

Just a quick thought. Did you open you oddments box and make sure the toggle between FRS and CB is switched to CB?

If it's on FRS you will receive CB, but will transmit FRS.

Also, because J&M supplies the entire package, it is likely that the Standing Wave Ratio is going to be real close right out of the box. In my installation it was right on the money.
 

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Discussion Starter #13 (Edited)
Thanks everybody

Hi, gang:

THanks to all who provided some insight in this new (to me) subject. This morning I went to my local bike club monthly breakfast and was fortunate enough to talk to a guy who is an amateur radio enthusiast. He volunteered to help me out and with his help we adjusted the antenna so that in channels 1, 20 and 40, the SWR is about 1.5. We had to take the antenna mount apart and solder the end of the wire, where the brass cylinder is on the end, back on to the wire because it was broken. Probably broke during installation. That allowed for a good ground and I was able to clearly hear and be heard when he rode his bike about 2 miles away from the house. I can't ask for more. We didn't have to shorten the antenna, but rather lengthen it by pulling it up slightly and tightening the allen screws holding it. I'm quite pleased with the results.

In response to BillyOmaha, I don't have anything in my oddments box but my CD player because I don't have the come system. This CB radio also works as an intercom, and allows the music, or whatever, to pipe in through the helmet speakers.

As far as how you say SWR in "español," it is something like "la proporción de onda estacionaria."

I really think that I ended up paying for the installer's inexperience, but what's done is done. As every cloud has a silver lining, I'll just look at it from the point of view that if something electrical goes wrong as a result of the installation, I would have some recourse because they, not I, messed up. It's not foolproof, but it at least makes me feel like less of a fool.

Thanks again to all of you for your help and guidance. I'm truly looking forward to meeting as many of you as I can at next year's CCR, or sooner if there's a tech session I can attend nearby.
 

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Joe tell me more about the system

Does it allow you to play the stock CD player and radio through it?
Does the intercom and CB mute the radio when they come on?
I also hear there is a plug in for an IPOD.
Do they all work with the systems RDS???

Thx!
larry
 

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Discussion Starter #15
Hi, Larry:

The answer to all your questions is yes. I hear the radio/CD player through the headsets and the outside speakers, although because of the proximity of the headsets to my ears, the volume is set such that I can comfortably hear the music in the helmet. That results in a low volume on the outside speakers, which, of course, can be raised to as loud as you want, assuming you adjust the headset output, if you value your eardrums. As far as the GPS/Cell-phone, there is a cable that replaces the one that comes with the unit, thereby giving you the capability to connect the cell, radar detector, etc. I'm pretty sure that an Ipod will work as well. You'd have to ask the people at Sierra Communications that question. http://www.sierra-mc.com/contact.asp I also don't know what you mean by RDS, so I can't asnwer that question either. Hope this helps.
 

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very cool

You've done what I plan to do, then I will use the CB to talk bike to bike. RDS is the volume adjust control based on bike speed.
Thx for the info, can't wait till I get mine!
larry
 

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Discussion Starter #17
Well, is that what the RDS is? In that case, the answer is definitely a yes. It does do that. You're all set. Good luck.
 

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Not quite. RDS stands for Radio Data System, and is what allows you to get artist and song info on your radio display for supported FM stations.

It is SVOL, or speed sensitive volume control that changes the radio volume based on the bike's speed. This is internal to the radio itself, so any changes it makes will automatically be heard on anything down stream (intercom, speakers, etc.).
 
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