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As so many have pointed out, CB's are behind the times, but my wife and I are tired of being the only ones in the group we've been riding with not linked in. I've read through so many CB post here I'm dizzy, however I'm not finding the direct answers I'm looking for. Just need an occasional short range solution.

Here's what I have: '05 LT with an Autocom Pro 7 Sport.

Here's what I think I want to use: Midland 75-822, maybe mounted with a RAM Mount System.

Here's what I don't want (at least for now): external antenna or run off bike's power.

So the big question is how to connect both speaker and Mic of the handheld to my Autocom? 2nd question, is it possible to setup a remote PTT for the wife? (note - I don't have the CB and don't really know what jacks are there)
 

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webwzrd said:
As so many have pointed out, CB's are behind the times, but my wife and I are tired of being the only ones in the group we've been riding with not linked in. I've read through so many CB post here I'm dizzy, however I'm not finding the direct answers I'm looking for. Just need an occasional short range solution.

Here's what I have: '05 LT with an Autocom Pro 7 Sport.

Here's what I think I want to use: Midland 75-822, maybe mounted with a RAM Mount System.

Here's what I don't want (at least for now): external antenna or run off bike's power.

So the big question is how to connect both speaker and Mic of the handheld to my Autocom? 2nd question, is it possible to setup a remote PTT for the wife? (note - I don't have the CB and don't really know what jacks are there)
Well, I'll give you some things to think about.

First, Autocom doesn't really recommend CB for their bike-to-bike configurations. The Autocom units tend to be sensitive to RF at CB frequencies, and often suffer from feedback on transmit (the RF gets into the amplifier circuits, is detected and amplified, then sent back out the mic connection to the radio (like sticking the mic from a PA right in front of the speaker). Some people have had no problems, others have not be able to make it work. It probably has a lot to do with the proximity of the antenna to the Autocom, transmit power level, grounds, and about a dozen other things (radio is after all, black magic).

Assuming you don't have that problem, the Active-7 has a radio connector (the light gray 5 pin) that is used for CB/FRS/GMRS. Connect your CB to this jack with the appropriate cable and you will be good to go in VOX mode (when you talk, the radio transmits, when you stop, it receives). This is probably not how you want to operate, since you don't want your private conversations between you and the pillion being broadcast to everyone else. You will want the Autocom PTT switch, which connects in series between the Autocom and the radio. This gives you a big PTT button to push when you want to transmit, but also has a small switch that lets you run VOX mode as well. I guess you could buy two and put them in series and give one to the pillion, but that is a rather pricey solution. For me, I would just put it in VOX mode when she wants to talk.

Since Autocom doesn't really like CB, they don't make a cable for the 75-822, you will have to roll your own if you are good with a soldering iron, or have someone make it for you.

Running the 75-822 on a RAM mount should work for short range, but you won't get much distance out of the rubber-duck antenna on top of the radio, probably around 1/2 mile. A real antenna will drastically improve your range. If you go with the BMW CB antenna, plan on spending a bunch of money.

If you connect the 75-822 to bike power, be prepared for a ground loop that will get you horrible ignition/alternator noise on receive (and maybe transmit too). You will have to install a ground loop isolator to fix that.

Still want to do this? I went through much of this installing my Ham radio on, strangely enough, my 05 LT with a Active-7 Autocom. You can read about it here:
http://www.bmwlt.com/forums/showthread.php?t=25181

If you just want to listen to what the other riders are saying about you on CB, that's pretty easy to set up.

-Scott
 

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Discussion Starter #3
Very thorough answer Scott - Thanks. To be honest, I guess I'm still debating sticking with hand signals.

I have read the Autocom CB Help Guide.
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If a CB is required, adhere to the following guidelines in order to better approach a positive result.
1. If the customer must use CB, handheld portable units work best
2. The CB MUST be powered by it’s own battery (not powered from the bike).
3. Using the LOW power setting on the CB usually has less RF feedback.
4. Using the supplied rubber duck antenna generally is less prone to RF feedback then an external, bike mounted antenna. In order to install a remote antenna, an SWR meter will be required in order to get a proper result.
5. Do not run interface wires near ignition coils, spark plugs, or any other places on the bike that may pick up RF noise.
6. Different locations on the bike may work better than others — be prepared to move the CB around for the best performance.
7. Installing an RF choke core around the (IL-09) lead, close to the 2-pin plug end will help absorb some of the RF noise. The amount of its effectiveness will vary.
8. Swapping the CB with an identical unit may resolve the issues
If after trying all of the above items the CB is still causing feedback. Keep in mind that CB’s are very inconsistent even among the same brand and model units. Swapping units may very well result in a higher level of performance.
9. Use the CB to monitor only
If the purpose is to monitor truckers for feedback on the road ahead we suggest that the CB is used with an audio lead to monitor only. An FM transceiver can then be interfaced for bike-to-bike communications.
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The handheld mounted on the handlebar would be a ways from the Autocom under the passenger seat. The antenna would be relatively high up and half mile range should be all I need for B2B.

What about this option of monitoring only? Would this just be a simple as connecting a speaker jack on the CB to the Autocom? Any better CB's to use if I go this route?

Brian
 

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webwzrd said:
What about this option of monitoring only? Would this just be a simple as connecting a speaker jack on the CB to the Autocom? Any better CB's to use if I go this route?

Brian
Yes, you would connect the 3.5mm speaker connection on the CB to either the cellphone 3.5mm jack on the Autocom, or to the 5-pin AUX cable on the Autocom if you are already using the cellphone jack. On the 5-pin DIN, use pins 2 and 5 per the attached picture (pin 2 connects to the sleeve of the 3.5mm plug, and pin 5 connects to the tip of the 3.5mm plug). Don't be tempted to put the CB in the top case, you WILL want to be able to adjust the volume and squelch!

I do not know which CB's are the best these days, I very seldom use CB.

-Scott
 

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