StarCom1 Digital to Yaesu FTM-10R Interface

[KenBobPDX]

After much trial and error, (and burned fingers from grabbing a hot soldering iron ) I have sucessfully interfaced my StarCom1 Digital to my Yaesu FTM-10R dual band ham radio.

I've sent the diagram to Joe at SpoiledBiker and to Yaesu tech support and will also post it here for anyone to use along with the description of how to interface these two superb pieces of equipment.

NOTE: You will need to make a custom cable to interface between the StarCom1 Digital and the Yaesu. That is what is described here.

I take no responsibility for damaged equipment, or burnt fingers as a result of following these instructions. They are posted here for your information only. This setup works for me. YMMV.

The six pin mini din cable that goes into the StarCom1 digital radio port can be purchased at most electronic parts shops. I got mine at Norvac Electronics supply. They are the same size as PS/2 mouse or keyboard cables.

You can find one here: http://www.pcconnection.com/IPA/Shop/Product/Detail.htm?sku=6003501&oext=1038A&ci_src=14110944&ci_sku=6003501 but if you shop around a bit, you can find them elsewhere for less $$.

HINT: Purchasing a premade 6 pin din cable and mapping the wires to the pins is a whole lot easier than trying to solder the pins into a 6 pin din connector yourself.

In addition to the 6 pin mini din cable for the StarCom side, you'll need to purchase the CTM-11 accessory cable to go into the back of the Yaesu radio.

For more information on the Yaesu FTM-10R go here: http://www.universal-radio.com/catalog/fm_txvrs/0813.html

For more information on the StarCom1 Digital go here: http://www.spoiledbiker.com/starcom1.html

To connect a Yaesu FTM-10R to a StarCom1 Digital system do the following:

Connect each of the 2 lines (green and blue) from CTM-11 cable to 390K ohm resistor. Tie the opposite ends of those resistors together and connect that to the same line as microphone in. Attach the microphone out line from the StarCom1 Digital to the microphone in line on the Yaesu (also attached to the end of the 390K ohm resistors).

When the PTT switch is thrown on the StarCom1 Digital, it pulls the microphone line to ground, signaling the Yaesu to open the transmitter. It sends a modulated microphone signal on the same line to the Yaesu microphone input.

You have to set the Yaesu FTM-10R microphone gain to LOW in order for it to work properly. Any other setting resulted in noise and the microphone cutting out during transmit.

When you speak into the microphone don't put it too close to your lips or you'll overmodulate the mic input. About 1/2 to 1" from your lips should do it.

Connect the speaker in on the StarCom1 Digital to the either the left or right speaker out on the Yaesu. (I used left)

Connect the ground on the Yaesu to the voltage 0 pins on the StarCom1 Digital.

See the attached diagrams for further details.

I've included the pin out diagram for the Yaesu CTM-11 cable, the StarCom1 Digital and a combination showing which pieces hook up to each cable.

This setup ROCKS! If you do the mod for the FTM-10R found here: http://www.mods.dk/index.php?ModelId=991&RadioRec=yaesu you can extend the reach into the GMRS and FRS bands. That way you can chat with others on the forum that don't have their HAM ticket and are using the FRS and GMRS radios for bike to bike.

DISCLAIMER: I'm NOT advising you to do this mod. I'm just saying IF you did do this mod, these are the things you COULD do.

GMRS is limited to 50W max power and FRS is limited to 500mW or .5W max power, the FTM-10R will only go as low as 5W, so if you XMT on FRS frequencies at low power you are doing it illegally at 10X the legal wattage.

Since FRS is an unlicensed band, with no enforcement, I don't know who would even know. However, if you do it, you do it at your own risk.

I was able to kerchunk a few of the repeaters around town and I'm looking forward to talking to a few of you on the road.

Here's a great set of pictures of Adam Koczarski's installation of the FTM-10R on his ST1300 http://koczarski.com/ST1300/YaesuFTM-10R/Pics.htm

Follow-up note: I've been checking with some other hams in the vicinity regarding the sound quality on transmit (it was not up to par) and after poking around a bit I discovered an impedance mismatch between the StarCom Digital and the Yaesu. I checked with the StarCom Digital MFR they advised me the impedance on the mic output line is only 600 Ohms! Yikes! The Yaesu wants a 2K Ohm mic impedance. It's no wonder my audio was overmodulated. I installed a 1.4KOhm resistor inline between the StarCom and the Yaesu, and it's cleared up a lot. I still get the alternator whine and spark plug noise, but they are in the background. The foreground audio is much better now. I've updated the attached wiring diagram.

K7KRH

 

[viperx]

Of course I would stumble across this thread the day AFTER I get my FTM-10sr hooked up successfully. Hahaha, life is short and bitter. Anyhoo, I wanted to add my two cents. I wired a microphone from radio shack into my helmet, a PTT switch into my handlebars, and the Line out from the Yaesu to a small amplifier in the front of the bike. Here is how I wired the PTT and electret condenser microphone into my FTM-10SR:

Orange Wire- Soldered to a non-polarized electrolytic capacitor, 10uF, Radio Shack Part # 272-999. Other end of capacitor soldered to an electret Condenser microphone, radio shack part # 270-092. (Capacitor soldered to white microphone output wire on condenser)

Gray Wire- soldered to a single 1k Ohm resistor, radio shack part # 271-1321. other end of resistor soldered to the condenser's red power wire. The condenser mike already was a maximum of 1k Ohm resistance, so I only used 1 resistor to increase the overall impedance to 2 k Ohms.

Blue wire- (4) 100k Ohm resistors were soldered in series, and one end of the series soldered to the brown wire, other end soldered to the input wire of a momentary ptt switch. Resistors are radio shack part # 271-1347

Green wire- (4) 100k Ohm resistors were soldered in series, and one end of the series soldered to the green wire, other end soldered to the input wire of the momentary ptt switch.

Red wire- Condensor ground wire and output ptt wire were soldered to the red wire.

Black and brown wires- not used, (I use the Line-out adapter to feed all audio to a speaker/amplifier setup I have on the motorcycle.


The audio is pretty darn good. This microphone setup cost me $10. Unfortunately the Yaesu does not support the FRS frequencies, so my wife's radio will no longer work as an intercom system anymore. Shoulda gotten a Starcom

 

[KenBobPDX]

The audio is pretty darn good. This microphone setup cost me $10. Unfortunately the Yaesu does not support the FRS frequencies, so my wife's radio will no longer work as an intercom system anymore. Shoulda gotten a Starcom

Good write up on how you got it hooked up. Actually the problem with the FRS frequencies lies in the FTM-10SR, not in the StarCom. The FTM-10R has a mod that will allow you to extend XMT ranges into GMRS/FRS.

 

[viperx]

Thanks for the tip. I tried their website but it won't send me the registration link Can you post the info here?

And by the way- absolutely kick-*** that you figured out how to hook up your radio on your own. Yaesu actually mailed me your notes when I asked them how to hook up a mike. I just copied someon'e post about an ICOM mike, and adapted it to the yaesu.

 

[KenBobPDX]

Thanks for the tip. I tried their website but it won't send me the registration link Can you post the info here?

And by the way- absolutely kick-*** that you figured out how to hook up your radio on your own. Yaesu actually mailed me your notes when I asked them how to hook up a mike. I just copied someon'e post about an ICOM mike, and adapted it to the yaesu.

Hey I just noticed you are up in WA. We're practically neighbors. What's your call? Do you ever get on the Evergreen Intertie? We should try and QSO some time.

The link to the Mod for the FTM-10R can be found here: http://www.mods.dk/view.php?ArticleId=3891

There is a link on that page to a PDF that has the information on it.

I looked for a matching mod for the FTM-10SR and couldn't find one. You also might try contacting another ST owner up in Washington by the name of Adam Koczarski.

I've been told that I've got a bad alternator whine and I may be over driving the input on the mic on the Yaesu. I need to experiment a bit with making sure I don't have an impedance mismatch. I'm still working on the interface.

 

[viperx]

Thanks for the reply. Kilo Foxtrot 6 Tango Whisky Kilo here. I can't login to that website with the link. I have tried and tried and tried. Any way you could email me the info directly? my eimal is viperxb AT yahoo.com

Your alternator whine might be fixable. There is a circuit I saw on the net that was for noisier mike lines that were longer than a few feet. I will try to dig it up. Cheers!