APRS Motorola CDM & TigerTrak TM-1+


Interface Motorola CDM & TigerTrak TM-1+ & Garmin GPS 16
TigerTrak TM-1+ RJ-11 Connector
Motorola CMD Accessory Connector
Pin Letter
Description
Pin Number
Description
A
Ground
7
Ground
B
Power
13
Switched Battery Voltage 0.5 Amps Max (Output)
C
PTT
3
Microphone PTT (Input)
D
RX Audio
11
Flat/Filtered RX Audio 350 mV RMS @ 3KHz Deviation (Output)
E
TX Audio
2
Microphone Audio 80 mV RMS @ 3KHz Deviation (Input)
F
Ground
7
Ground
N/A
N/A
10
Ignition Control (Input)
  • Insert jumper JP1 – Provides power to Garmin GPS 16 on pin # 9 of DB-9 connector.  Remember to remove this jumper prior to connecting TM-1+ to a computer for programming!
  • Insert jumper JP2 – This will bypass the front power switch causing the unit to begin operating immediately when power is applied to pin B of the RJ-11 connector.
  • Solder a short piece of wire from RJ-11 pin B (Inner leg of JP-3 jumper) to external power input.  This will allow CDM pin #13 to power TM-1+ and Garmin GPS 16.
  • Adjust front level setting to full clockwise.  You may need to increase accessory microphone gain (39 dB seems to work fine) in the Motorola software to obtain necessary deviation.
  • If higher output level is required from TM-1+, replace R19 (factory set at 324K) with a value around 120K.  R19 can be lowered down to 10K for a 1V P-P output into 600 ohms.


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