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Windows software for Motorola GM-300

WINScanner for Motorola GM300

&127; Frequency range from 140MHz to 150MHz
&127; Select Step between 12,5kHz, 25kHz and 50kHz
&127; Step Up and Step Down
&127; Scan Up and Scan Down
&127; Dual Watch
&127; Repeater function (Split)
&127; 2 Memory Bank with 100 memories
&127; Signal Meter
&127; 1MHz Spectrum Scoope

System Requirements:
&127; IBM PC compatible
&127; Windows 16/32 bit and Windows NT operating system
&127; 1 MB of RAM, 1 MB of free disk space
&127; Motorola GM300 Software
&127; Motorola GM300 VHF-Radio

&127; Few component`s
&127; 1 pcs. 25-Pin D-SUB Connector
&127; 1 pcs. NULL-Modem Cable

The connection to Printer port.
25-Pin Printer Connector
Install a 25-pin D-SUB Male connector on the President James bottom cover, and use a NullModem cable to the computer`s printer port.
See Radio interfacing to Printer Port for more information about using PrinterPort.

PinPrinterPortDirectionUsageConnection to:Active H/L
2Data 0Out to radioPLL ClockU101 Pin 9HIGH
3Data 1Out to radioPLL DataU101 Pin 10HIGH
4Data 2Out to radioPLL EnableU101 Pin 11HIGH
5Data 3OutTrig to OscilloscoopeNot in useHIGH
8Data 6Out to radioAudio MuteHIGH
9Data 7Out to radioReset to A/DA/D-ConverterHIGH
10ACKIn from radioPTT SwitchLOW
11BusyIn from radioSquelch ControlHIGH
12PaperEndIn from radioA/D outputA/D-ConverterLOW
18GroundGroundU101 Pin 6

MC145158  Modification Circuit

You have to do some small modification around the MC145157 PLL-Circuit (U101). Cut the traces to Data, CLK and ENB inputs on the PLL and insert 3 pcs. 4,7kW resistors across the cutted traces. This is to protect the CPU from be destroyed when the radio is connected to the PC printerport.

Analog to Digital Converter
Analog to Digital Converter
To use the S-Meter you will need a AnalogDigitalConverter.
This is a simple ADC for reading the S-meter value. Connect the S-Meter signal to the Input, and the Output to the PaperEnd signal and Reset to Data 7 on the printerport.
Use a BC107 or similar NPN Transistor (Not critical).

Frequency range
The frequency range is set to 140MHz to 150MHz.
When you first time start up the GM300 software, it`s will create 3 files;
Memory1.TXT and
In the file Setup.TXT you will find the that the 2 last lines is the Minimum and Maximum frequency for the software.


You can change this values for the software..

User Manual

&127; GM300.EXE and install the file under C:\Motorola\
&127; Inpout16.DLL and install the file under C:\WINDOWS\SYSTEM\
&127; HMeter.VBX and install the file under C:\WINDOWS\SYSTEM\
&127; VBRUN300.DLL and install the file under C:\WINDOWS\SYSTEM\

Saving files:
PC: Right-click on link and choose "Save File As"
Mac: Click and hold on link and choose "Save File As"