/ Motorola Gm300 Radio Doctor Download UpdateStar is compatible with Windows platforms. UpdateStar has been tested to meet all of the technical requirements to be compatible with Windows 10, 8.1, Windows 8, Windows 7, Windows Vista, Windows Server 2003, 2008, and Windows XP, 32 bit and 64 bit editions. Recently, I was given a couple of Motorola Radius GM300 mobile radios, a GM350 and a set of three GP320 one-channel handhelds. Pin1 pin2 pin3 pin4 pin5 pin6 pin7 pin8 mic ground mic ptt ptt ground up down common up/down dc volts. Download Radio Users Manual of Motorola RADIUS GM300 for free. Support Windows XP, Win 7 Win 8.

Programming / Service software for the Motorola Radius GM300

It has been pointed out to me that this software only works with the GM300 so I have adjusted the page.

Motorola Radius Gm300 Receive Issues

After searching for the genuine Motorola program I came across Motorola Radius GM300 Radio Doctor. This program runs fine under Windows XP and will do all the functions that the genuine Motorola radio service software does. Here is the main screen.

Motorola Radius Gm300 Radio Doctor

See a video of the software in use

If you want a copy of Motorola Doctor software just join the following group

You will also need a simple interface to connect the radio to your PC. You can make your own or just search on Ebay for 'GM300 programming' or make programming interface from below 'at your own risk'

GM300 programming connection When looking at the radio here are the numbers

As you can see to make the programming interface for your GM300 is very basic.

Connection your Motorola GM300 for Echolink or IRLP etc.

If you want to use the COS/COR output from your GM300 the COS/COR on pin 8 is (active low). Many interfaces need a COS/COR input that is (active high) at 2 to 5vdc. You can make up a circuit to convert the output from pin 8 or take a COS/COR output from inside the radio that will give you a (active high) output. You will need to access the logic board on the underside of the radio. Remove the front of radio and the bottom cover and lift off the RF shield. See photo below.

Motorola Gm300 Programming

If you use thin wire you will be able to feed this out the edge of the 16 way connector. I tied a knot round the connector on the board to stop it being pulled off the board. Take care not to short this COS/COR out because it will damage the radio.