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Saturday, March 15, 2014

Motorola GTX 900 Accessory Connector

Greeting all here is a write up on the Motorola GTX 900 Accessory Connector

The connector you can buy from Digi-Key

      Digi-Key Part Number 104422-1-ND, 
      Manufacturer: TE Connectivity 104422-1

The pins for the connector

     Digi-Key Part Number A3007-ND
     Manufacturer: TE Connectivity 1-87309-3

Back End View of Connector

← Latch
15 13 11 9 7 5 3 1
16 14 12 10 8 6 4 2

GTX Mobile Accessory Jack Pins and Signals
Pin # Signal Name Description and Usage
1 EXT SPKR - Connect to an external speaker with pin 16
2 EXT MIC AUDIO Microphone-level audio input
3 EXT PTT Push-to-talk input
4 EXT ALARM Active low output to drive a relay
5 FLAT TX AUDIO Line-level audio input
6 SCI DATA IN Not used
7 GROUND Ground for PTT and audio - NOT FOR SPEAKER
8 SCI DATA OUT Not used
9 EMG SWITCH Low input activates alarm functions in radio
10 IGNITION CTRL Must be pulled high to let radio turn on
11 FLAT RX AUDIO Flat receive audio output
12 GP I/O Not used
13 INT SPKR Connect to pin 16 to activate internal speaker
14 HOOK Low input to activate RX PL/DPL
15 RSSI BUF Analog output of rcvd signal strength: 1.5 - 4.5 VDC
16 EXT SPKR + Connect to an external speaker or pin 13

 GTX1 works with early model GTX

GTX2 works with late model and LCS2000

Example late model with ext speaker