Cellular Phone Interface Comparison.

Walker-Kennedy(pre-upgrade unit)-Wong

My Setup on my Wing.

My job often requires that I be on-call and available via pager. Unfortunately, having to look for pay phones was a major pain and a definite damper on a good ride. The following is a comparison/review of 3 Cellular Phone Interface units that I have personally used. The following is strictly my own opinions and is not designed to slam or degrade any manufacturer or person, just simply my own thoughts on quality, design and real time use.

I have been using and testing interfaces for about a year and the above photo is of the 3 units I have mounted and used on my Goldwing. From Left to Right they are:

Walker CellSet

Kennedy CellSet

Wong CellSet

I will start with the unit I first used and that being the Kennedy CellSet.

At the time I saw this there were a couple of units on the market. Non of which interested me because it locked you into a specific phone, or required the phone to be permanently mounted on the bike. The Kennedy (at about $79.00) was supposed to be universal (with some limits), small and easy to install. I had just purchased a new phone a Nokia 6185. The Kennedy set is designed to plug into a phone that has a sub-mini stereo jack. The Nokia uses a plug in device that plugs into the bottom of the phone and has the jack on it. I purchased the Kennedy Set, the small interface, a car mount and a charger that plugs into a cigarette lighter. I mounted everything, the Kennedy plugs in-line with your existing intercom cord, and it worked great. I thought I was in seventh heaven because I could now ride all I wanted and not have to worry about being paged and finding a phone. The quality of the Kennedy unit was of good quality, totally waterproof and rugged. It interfaced with the intercom system and did not interfere with any of those systems. My only single complaint about the unit was that it was missing 2 things. 1. It did not have any way of adjusting the audio level for individual phones and 2. It did not have the dust boot cover over the interface cord. This caused me some issues because when I wash the bike I don't want water getting into the plug. Kennedy told me they were working on correcting that and I even asked if there was going to be an upgrade path and or kit to buy to correct it. They told me yes but even in their 2nd generation interface it still does not have the dust boot but I am to understand it does have an audio adjustment.

After a while I got tired of having to unplug the interface, unplug the power cord and make sure I did not lose the headset adapter or break it. Nokia has a Car Kit they sell for anywhere from $100.00 to $175.00 depending on the day of the week, the sales guy and where you buy it. It is a compact system that has a cradle and an interface unit that provides power to the phone for charging as well as speaker and mike. It is handled with 1 cable from the cradle to the interface box and 2 outputs for external speaker and mike. I decided to try and make the CellSet work with this unit and ended up hard wiring a handsfree adapter into the unit and plugging the Kennedy into that. This worked well and I stayed with this until the Wong CellSet came out.


Wong CellSet

The Wong set is one that was made by a guy from Taiwan. It is a home made unit and serves the same function as the Kennedy. The Wong set was for $30.00 and I figured I couldn't really go wrong with this at that price and I purchased one. After it finally arrived I installed it the same as my Kennedy was installed and it worked almost as good. There was an audio adjustment you could do with this one and was a little bigger then the Kennedy.

I did not like the Wong unit because of many reasons.

It seemed to have an oscillation sound to it, meaning it would switch back and forth, quickly, from mike to speaker (or sounded like it was) so conversations were often choppy.

It used all white. This really bugged me because were it not for my Kennedy RadarSet I would have had this white cord sticking out of my fairing pocket.

It also did not have a dust boot cover.

I tried using the Wong but could only deal with it for about a month before I took it back out and put the Kennedy unit back in place.

Overall it was a nice try but poor quality and bad choice of color for the cables.

Walker CellSet

I don't know if it was a posting I did on WOTI or what it was, but at the time I replaced the cradle handsfree adapter with the carkit it seemed to start a flurry of desire for others to mount cell phones on their bike, so along comes Mr. Carroll Walker. An avid HAM enthusiasts and MARC (Motorcycling Amateur Radio Club) http://members.home.net/ve6hgw/marc/ member. Carroll is also a genius when it comes to electronics and making audio equipment, lights or anything else for the Goldwing work better. He decided to design his own interface unit. He also has a Nokia with a carkit. Carroll provided all the information anyone could want for his interface design and helped anyone and everyone that asked to make sure it worked properly.

Carroll's design is different then the Kennedy or Wong in that while it interfaces with the intercom it does not operate with the intercom. This means that when your on a phone call the rest of the intercom is disconnected so when I am on a call the Radar Detector, CB, HAM radio and passenger is all locked out until you hang up the phone. There is a optional wire that you can put on a switch to put the phone in standby while your on a conversation to allow you to use the CB, HAM or talk to your passenger.

Carroll's design is great. It has the best quality out of any of the others and the most reliable. With the Walker unit most people do not know or believe that I am on a Motorcycle, on the highway, 70 mph talking on a phone. The Walker set is bigger then the others but it can be squeezed into a smaller box when you build your own. The Walker set is also designed specifically for the Nokia Carkit but changing it to work with any other type of Carkit should not be a big deal considering the only thing you MIGHT have to change is the power feed between the Walker and the Nokia interface box.

Below is a photo of the Walker interface sitting ontop of the Nokia Carkit interface.


The unit above is Carroll's own unit and is a different size then mine which shows you that you can squeeze it into a smaller box. The Nokia plugs it power into the Walker set and the Walker set gets power from the bike. The Walker set has 2 cords that plug into the Nokia for Speaker and Mike and has the intercom input and output and it plugs inline with your existing intercom system. Note the dust boot on this unit.

Schematic for Walker CellSet

I have been using the Walker unit for over a month and I could not be happier. I have all the features of the Carkit along with the convince and the quality of clarity. If Carroll were to market this unit I am sure he would make a good dent in the market.


A word about the J&M Unit http://www.jmcorp.com/

J&M was the first unit I had ever seen that interfaced a Cell Phone to the Goldwing. The first one I saw was years and years ago when I had a 1984 Aspencade. I was at a Motorcycle show and saw their unit mounted on a 1500 using a NEC P200/300 phone. I did have that same phone at the time but the unit J&M was selling was VERY EXPENSIVE. The Carkit for the NEC was over $300 at the time and I believe the J&M interface was someplace in the $600 to $700 price range.

I did at the time purchase the NEC Carkit and I wired it up to my intercom system back then and it worked OK. When I got my 1998 1500 I again needed a phone setup and I looked to J&M. I still had my NEC P300 phone but J&M did not have the Carkit anylonger since they discontinued it long ago. I already had 3 Carkits for my NEC in 2 cars and my Motorcycle and all J&M was selling was a interface kit that worked with the Motorola Startac phone. It was again VERY expensive and I decided I was not going to go with a phone interface that was stuck with one phone.

While I respect J&M and I believe they put out great products that are of high quality, they stand behind their work and they have great customer support, they are a bit pricey. This kit above, which now interfaces with most any phone like the 3 I tested, is at a $300.00 price range. The only difference I see here is that this kit also interfaces with a radar detector and this kit will work as a stand alone unit so it would work on basically any Motorcycle out there. For the $300.00 it did not seem worth it to me.


I again stress that the above is my own personal opinion based on personal usage. Use your Cell Phone while driving smartly and when needed pull over. Your mileage may very. Questions and comments are always welcome.

04/22/02 Update

I have received allot of email from folks asking for contact information for Mr. Walker and or wanting information on how to make the Walker Cell Set work on different phones. The Walker system is designed for a Car Kit. A Hands Free Kit is one that plugs into the phone and allows you to use a headset to hear and speak into the phone. A Car Kit is one that is designed with external speakers and microphones and a cradle for the phone to sit in and normally a built in power/charger is included.

I cannot stress enough that the 2 are very different. The walker design is designed to use the Car Kit mute function. This function is available for cars with radios/stereos that have a mute function. The your phone receives a call or you place a call it activates the mute line and mutes your car radio. The Walker design uses the mute line to activate the relays that switch your helmet headset from the intercom to the telephone. I personally only know of 2 manufactures that make true Car Kits that being Nokia and Motorola. The only Nokia Car Kits I am aware of are for the 5000/6000 series phones. Motorola makes a Car Kit for the Star Tac, however a friend of mine had a Star Tac phone and purchased the Car Kit and upon receiving it found that the kit was way to big and bulky to be useable on a motorcycle.

The way the walker system works. Referring to the above schematic, you will see that the 5-pin headset is wired through a relay or series of relays that in their inactive state they complete the connection to the motorcycle intercom system. When the phone received a call or when placing a call the mute line is activated, meaning 12 volts is supplied to that line. When that happens it supplies power to the relays, energizing them and causing the relays to switch from the intercom system to the phone. The schematic shows the 5 pin connections for a Honda Goldwing. It also shows the tip and ring connections for the telephone. If you have a different motorcycle, and or a different type of phone, you can use the basics of the schematic to design your own system using the same principle. You will have to figure out, on your own, what lines on the phone are tip and ring for both the microphone and the speaker. You will also need to figure out what pins in your helmet headset go to what on your motorcycle intercom system.

You do not however, need to have a motorcycle intercom. You could actually put this type of system on any motorcycle simply by wiring a helmet headset direct into the phone. I regret that I cannot simply provide Mr. Walkers contact information as he would be just as flooded with emails as I have been. I can answer most of the questions provided to me if you have specific questions about the Walker Schematic and I am happy to help you brainstorm ways of making it work with your specific phone and motorcycle.


Happy and Safe Riding.