Connection to Motorola GM300

Connection to Motorola GM300

8-Channel Radio Pin out
1. External Speaker Negative
2. Microphone Audio
3. Microphone PTT
4. External Alarm
5. Flat Transmit Audio
6. Not used
7. Ground
8. COR output Active low
9. Emergency Alert Input
10. Ignition Control Input
11. Discriminator Audio Output
12. Not used
13. Switch A + Sense 0.5A Max
14. Remote Hook Switch input
15. Internal Speaker Positive
16. External Speaker Positive 16-Channel Radio Pin out
1. External Speaker Negative
2. Microphone Audio
3. Microphone PTT
4. Programmable output
5. Flat Transmit Audio
6. Programmable Input
7. Ground
8. Programmable I/O
9. Programmable Input
10. Ignition Control Input
11. Discriminator Audio Output
12. Programmable I/O
13. Switch A + Sense 0.5A Max
14. Programmable I/O
15. Internal Speaker Positive
16. External Speaker Positive

Above are the Pin-outs of Motorola GM300 Accessory connector. This connector can be ordered through
Motorola dealers. Hardware Kit that includes 16 connector pins, and housing - Kit #HLN9457
Connection to SRP-1
Make up a link cable as following table
SRP-1 Connector Pin GM300 ACC connector Pin
Pin 2 (+12V)
Pin 3 (RX AF)
Pin 4 (TX AF)
Pin 5 (PTT)
Pin 6 (SQLS)
Pin 9 (GND) -
-
-
-
-
- Pin 13 (Switch A)
Pin 11 (Discriminator AF Output)
Pin 5 (Flat Transmit Audio)
Pin 3 (Microphone PTT)
Pin 8 (COR or Programmable I/O) **
Pin 7 (Ground)
** For the 16 Channel versions, Pin 8 must be programmed as "PL/DPL & CSQ Detect -
Active Low" using GM300 programming software. Other programmable Pins should be disabled.
When you use DP/DPL you need to ground the Hook terminal on Microphone plug (Pin3).

Jumper position on SRP-1
Set three jumper pins on SRP-1 board as follow.
JP1 - Remove Pin
JP2 - Insert jumper on Pin 2-3
JP3 - Insert jumper on Pin 1-2
Cut R22 on SRP-1 board