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Waiting for the weather to get better I've been mulling over the CB thing again.

My options have been:
1. Kennedy FRSset
2. Air Rider Add a Radio

John from Kennedy said he has a problem with feedback with hand held CB's with his set and Air Rider says they work fine. Personally if I'm going to buy something I like to give it to the little guy (kennedy).

However I came across this:

http://www.marc-hq.org/40.technotes/40-40.t1996-02.r01p01.htm

Which is someone connecting their Hamm radio to the bike. I have everything I would need to do exactly what he did. However, I don't see the plug that he speaks of. It is not the plug that hooks into the back of my radio?

Anyone know where this plug goes?

thanks

steve 90 GL-1500
 
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Hey poffy74 :waving: Your very welcome to the forum and visit often. :clapper: I see you have (3) three barrells of "Mana" and you only joined four days ago.:stumped:

Did you give a brown envelope to wexman by any chance. :whip: This guy is known to accept back handers when the going gets tough. :stumped:

:leprechaun: :18red: :leprechaun:
 

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poffy74 wrote:
John from Kennedy said he has a problem with feedback with hand held CB's
--------------------------------------
However  I came across this:


Which is someone connecting their Hamm radio to the bike.  I have everything I would need to do exactly what he did. However, I don't see the plug that he speaks of. It is not the plug that hooks into the back of my radio?


steve 90 GL-1500
1.) Yes he has, and J&M have and everyone else thats tried it, and they will never be able to fix it. Motorcycles are the worst platform for RFI there is. J&N had this mess in the 1500s and released a bulletin, but that was the end of that, never fixed it. Anyone can "design" such a system from an audio and switching standpoint (like the page you quoted) but the RFI problems are even beyond many degreed EE's. The feedback problem is variable, and largely depends on the transmit antenna system and how well its tuned.

2.) Im a Federal Radio operator, electrical engineer, former Ham operator thats put both 2 meter rigs and integrated CBs on both 1200 and 1500. Been there, done all that.

I built an integrated CB from a cheap Radio Shack CB and put it on a 1500A. Worked well.

The Hams statement:

"There is no reason you can't replace the 2-mtr radio with any other transceiver or CD player, etc."

is in error. There is a reason, and it has to do with transmit frequency and radiated power. The 2m transmitter and CB are on greatly different frequencies (BC = 27 MHz, 2m = 144 MHz), and the 2m rig is FM, which greatly reducs feedback problems. CB transmitters are AM, so the feedback, if in phase, adds to the mic signal and drives the system into oscillation. The CB transmitter is a 4th harmonic of the FM band.

The only way "they" can cover the problem up is to reduce transmit power, and thats violation of Federal Law without having running the transceiver through Type Acceptance with the FCC.

This was such a ____ of a problem I ended up picking the brains of a certain military "3C" lab for help. I eventually eliminated the oscillation problem but it took 4 years.

3.) The connector is the plug that exits the back of the stereo, its a special connector for the CB with high force box terminals. Need luck to find them now, I had trouble doing so 10 years ago when this setup was recent production.
 

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poffy74 wrote:
Which is someone connecting their Hamm radio to the bike. I have everything I would need to do exactly what he did. However, I don't see the plug that he speaks of. It is not the plug that hooks into the back of my radio?

Anyone know where this plug goes?

thanks

steve 90 GL-1500
Steve, the Ham is referring to the connector to theCBswitches mounted on the left handlebar of Aspencades that haveCB installed.
 

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RF interference is one of the toughest parts of electrical engineering, one of my specialties.

This drove J&N and his dealers nuts. Lots of returns and problems at rallys from feedback and squeal. Theyd install them on 1200s and the units wouldnt even make it off the rally site before they started squealing. Wasnt their "fault," it just happened. The equipment works great on the test bench, but when its installed on the bike, all "you know what" can break loose.

Panasonic (Hondas OE Japan supplier on the 1200) has the heavy duty engineering to make it work, but the rest of us poor souls are in trouble. Even Hondas CB units squeal out when the connectors get old. CB antenna puts out a very strong RF signal right on top of all the bikes wiring and its a nightmare to sort out. :(
 

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in my research trying to amplify a dynamic mic to get good modulation, i have concluded that the culprit is the mic element itself. it is a perfect receiver. it has lots of windings to collect the cb's AM signal, filter out the carrier and send the transmitted voice right back into the system, thus the feedback. that's why the new handlbar mount jm unit uses an electret mic element.
 

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jjambor wrote:
in my research trying to amplify a dynamic mic to get good modulation, i have concluded that the culprit is the mic element itself. it is a perfect receiver. it has lots of windings to collect the cb's AM signal, filter out the carrier and send the transmitted voice right back into the system, thus the feedback. that's why the new handlbar mount jm unit uses an electret mic element.
I never knew that. I wonder if the other headset makers should take note of this?
 

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Here's an observation that may shoot down my mic theory: Many 1800 users have successfully added an aftermarket cb to their bike with out feedback. in fact, i don't recall that i have ever had a return from an 1800 user and our frset equipment. However, I have never had any luck with any other intercom system unless one breaks the loop and connects the headset mic directly to the cb mic input.

don't get your hopes up: this configuratiion results in poor modulation.
 

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jjambor wrote:
Here's an observation that may shoot down my mic theory: Many 1800 users have successfully added an aftermarket cb to their bike with out feedback. in fact, i don't recall that i have ever had a return from an 1800 user and our frset equipment. However, I have never had any luck with any other intercom system unless one breaks the loop and connects the headset mic directly to the cb mic input.

don't get your hopes up: this configuratiion results in poor modulation.
Makes one wonder if it's not at least partially the result of an impedance mismatch between the mike Zoutand the bike'sZin or theZin of the CB and the Zout of the bike since it works with the mike connected directly to the CB. That's a pretty common cause of audio distortion, feedback, and low output.

:stumped:
 

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the way our frset works is this. radio audio output is isolated and attenuated and placed on the mic input line of the intercom system. in a sense, a virtual passenger headset mic.

radio mic audio input is pulled off the intercom's left headphones output. it too is attenuated and isolated. what happens when you transmit is your voice is amplitude modulated and broadcast...but the am signal is received by the mic element and/or intercom system and fed back into the intercom... boom! feedback.

our cbset was different; radio out audio was fed into the intercom the same way, but when you keyed the cbset and radio, the drivers microphone was disconnected from the bike intercom and connected directly to the radio mic input. no feedback loop but the problem was poor modulation.
 

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How bad is this feedback? Scale of 1 - 10?

I've never been a picky person. With bike to bike comms I've always been happy with "my message got across". The people I ride with I have ridden with for a long time. We were able to communicate without the CB. In the past year we decided it would be better with CB.

One has a JM (on an ST) - Another had a really bad Cobra set up and I was taking the output of the CB and feeding it isolated into my home made amp. For mic I was using a RadioShack Throat mic.

My only goal is to get CB comms working "ok" with the Goldwing system. i.e. "I need gas", "hey did you see that cute girl in the Honda Civic" ... etc :cool:

I like paying the small guy. That is why I was leaning towards using the FRSset with a Maxon handheld. What do you think?



steve
 

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it can be a 10. just awful.
 

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Jon, thats interesting about the mic. Ron Wylie has an article on Steve's site about making headsets and he plumpled for the electret mic as well. I haven't seen Ron on the forum for a while (since we changed over to the new one here last year in fact) so I hope he is keeping well.
The article is here http://www.goldwingfacts.com/DIYintercom.htm
 

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Would using an Electret mic (condenser) make make this problem go away? or does it just minimize it.

What is the best solution to be able to use CB?

If its disconnecting the mic from the bike with a relay or gate how would you boost the modulation?

Or should I just give up and hook all my stuff into my old amp (like I did before) and run all of that through a casette adapter and continue to use a throat mic?

Is the CBset still available anywhere?

*hands in the air* What do I do????????
 
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