AOR AR16 interface
The serial connector is a 1/8 stereo connector, tip= RX data to radio, ring= TX data from radio, sleeve= gnd. As I referenced earlier, the internal supply is nominally 3.3 volts, so you will need a TTL (3.3v) to RS323 converter. I have used a maxim part (they have several that will work with 3.3v), you just need 1 TX and 1 and one RX channel. Their data sheets should provide basic hook-up information. Depending on the device you use, you may have to provide an external supply to run the converter if you can't get enough power from the serial port.
good luck
tom