Remote Control of Icom Marine Transceivers via PC Com Port

Icom M710 M710RT M700Pro


It is possible to remote control (e.g. have the computer change frequencies and modes) on your Icom M710, M710RT, or M700Pro by using a COM port (aka: RS232 port, or serial port).  Remember that most laptops only have one COM port, and you already need one COM port to connect to your HF Modem.  So to do this form of remote control you will need to add a second COM port.  While you are adding ports, you should go ahead and add a few COM ports, because sooner or later you will also want to hook your GPS nmea output to your laptop as well.  You can buy USB adapters that provide up to eight additional COM ports .   There are lots of manufacturers of USB adapters that provide a single additional COM port.


The following is an excerpt from the Help files that are part of AirMail:


COM-port remote control for Icom Marine Transceivers:

Icom M710 radios and some M700pro radios are equipped with a 9-pin connector for NMEA control. The connections are not the same as RS-232 but can be connected to a computer serial port with a suitable cable. Some M700pro radios do not have the NMEA connector, but they have a 1/8" mini-phone jack which can be connected to a serial port with an appropriate level converter (see below). 

M710 (and some M700pro's)
The 9-pin NMEA "Remote" connector (labeled "DSC" on some models) can be used for remote control of the transceiver mode and frequency with any HF modem type, by using an additional computer serial COM port. NMEA signal levels are a differential version of RS-232 voltage levels, approximately +8 and -8 volts. With appropriate wiring the "+" NMEA connections can be connected directly to a RS-232 serial port. (Note that the "-" input must be grounded as a reference, but do not ground the "-" output). 

A cable to a standard PC serial port can be made up as follows:

ICOM 710---- Computer serial port

(9-pin male) --- (9-pin female)


NMI+ 5-----------3 TxD

NMO+ 7-----------2 RxD

NMI- 6-----------5 GND

GND 9------------5 GND


In order to use the NMEA interface, it must first be selected using the front-panel "Set Mode" functions (turn power on while holding down the "Func" and "1" buttons). Select the "REMT-IF" (remote interface) setting and change it to "d-Sub" (or "RS-232" on some models). Also check that "REMT-ID" is set to "01" (or enter the REMT-ID number into Airmail below). 

AirMail Options Settings: 

Modem (TNC) connection: (appropriate for the modem)

Audio Tones:

Center Frequency: 1500
Check "USB
TxD: 20 ms

Amplitudes (SCS PTC modems only): as appropriate, start with 130/170

Radio connection: 

Check "Direct via COM port", enter the appropriate COM port for the radio connection
Radio type: Icom-NMEA:
Baud: 4800 
VFO: not used
Icom Addr (hex): 01 (or to match radio setting)

Dial offset: 00 

Note: Click the Modes button and verify that the settings match the radio's mode labels as you cycle the radio through each mode. 




M700pro's that do not have a "Remote" jack:

Some M700pro radios only have the 1/8" TTL-level jack labeled "Clone". This can be used directly with the PTC-II HF modem but requires a level converter for use with a COM port (such as the Icom OPC-478 cable available from Icom dealers). This connector is normally used by dealers for radio setup but can also be used for NMEA remote control. Setting up the radio and Airmail is the same as for the M710 above (including selection of "d-Sub" or "RS232" for the radio's REMT-IF setting). 

Note that some Icom documentation refers to this as a CI-V jack, but it only works with NMEA data formats. 
Also note that Icom does not officially support the use of this jack for remote control, and if you go to Icom with questions they will disavow all knowledge. While this connection works at the time of this writing it is also possible that Icom may make some changes, which will make it incompatible. Please send us an email if you have any questions or difficulty. 

AirMail Help 1997-2008 Jim Corenman ke6rk