Mar 25, 2016. » rss software motorola gm300 windows 10 » motorola gm300 series dowload » gm300 win7 » professional gm300 download win7 » gp 300 gm300 programming software cps » gm300 cps software » gm300 programming software » software gm300 » software para motorola xt303 motorola » motorola software update motorola.co.uk. May 05, 2019. I joined the Yahoo Group and downloaded the Radio Doctor software from the files section of the Yahoo Group. I also ordered from eBay a '3 IN 1 Programming Cable' which is an RPC-M300 or a clone of that unit (see photos below to find a similar unit) which had the RJ-45 Crystal plug or whatever Motorola calls their RJ45 connector on the GM300 radio.
Introduction.
The Motorola GM300 can be re-programmed quite easily to allow use on our Amateur Radio bands. The radio is made in both a VHF and UHF versions, and makes an excellent 2mtr or 70cms mobile/base station radio.
Most of the radio's I have worked on have originally been 8 channel units. These can be modified to operate on 16 channels quite easily.
The programming interface can be made for a low cost. All it consists of is a RS232 to TTL level converter, that connects between the serial port of your PC and the radio's microphone socket.
Amateur Radio Conversion.
The radio requires the Motorola Software which can be found if you ask around or search for it on the FTP sites on the Internet. If you can't find it then try your local Motorola dealer who should be able to help at a small cost.
You also have to make an interface, or purchase one.
To program the radio onto the Amateur band, you can find some versions of software that have been hacked into allowing frequencies to be entered to bring the radio into the amateur bands which normally are just bellow the original working frequency. However this depends on your version of software, if it's a un-hacked version then you have to press the key down when entering the frequency. You must release the key when entering the decimal point. For example to program 433.500MHz you will enter the following: $££.%)) on a English layout keyboard. (This is 433.500 with the held down. Fill all of the 0's in the frequency field. This example is the same for both the VHF and UHF GM300's.
16 Channel conversion. (for 8 channel radio's only)
To program the radio for 16 channels all you need to do is edit a file called GM300.MDF. You do this with the help of a Hex editor such as Hex Workshop. The file you need to modify is called GM300.MDF and can be found in the main directory of the Motorola software. Keep a backup of your original GM300.MDF file, just in case you make a mistake.
I have made a small video that shows the Hex Workshop screen during the modification. This should help you understand the procedure of editing the file which when complete will give you 16 channels. Java 7.45 for mac. Click below to download.
Procedure
- Get a copy of Hex Workshop
- Start the Hex Workshop program and open the file GP300.MDF to begin editing.
- Go to 'Tools', and the 'Generate Checksum'.
- Make sure 'Entire Document' and also 'Decimal' are ticked. Then press 'Generate'.
- Look in the 'Checksum-16' box, in my version of software for example this results in a checksum of 5514. (yours may be a different number depending on the version of Motorola software)
- Write this number down, as you need it later.
- Press 'Cancel' to return to the main window and your next step.
- Go to 'Edit' and then 'Find'. A pop-up window appears.
- You need to enter the model number of your radio. For e.g. M34GMC00D3AA.
- When you enter the model number leave off the last two letters(AB on my radio).Make sure 'ASCII' is ticked.
- When you press 'Find Next', you will see your model number highlighted.
- If you count 8 numbers after the highlighted section, you should see the number '08' as long your radio is originally a 8 channel set.
- Edit the '08' to '10' (note 10 in Hex is equal to 16 in decimal).
- You now need to edit the start of the program, to allow the software to run.
- In the first few lines look for a Hex number that you can easily take away 8 from.
- In my software at address 00000040 you will see the number '78' on the right.
- Edit this to be '70'.
- Now you must do a final checksum and make sure it equals the original value.
- If this is the same, then replace you original file with the modified file.
- Try to reprogram your radio with the extra 8 channels to give you 16 channels.
Motorola Gm300 Programming Software Download
https://ameblo.jp/33ciopersi-bek6/entry-12650730535.html. 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.
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.
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.
Motorola Gm300 Repeater
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 Microphone
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.
