Garmin GTR 200, Installation Manual

Page: 51 / 85

190-01553-00 GTR 200 Installation Manual
Rev. B Page 4-5
4.9 Pilot/Copilot PTT Inputs
When pulled low, these inputs allow the audio that is present on the PILOT/COPILOT MIC IN to be
transmitted over the radio.
Active-Low discrete inputs are considered active if either the voltage to ground is ≤ 3.5 VDC or the
resistance to ground is ≤ 375

.
These inputs are considered inactive if the voltage to ground is 6.5-33 VDC or the resistance to ground is
>100 k

.
4.10 TX Interlock
TX Interlock Out is an active low output that indicates that this radio’s (GTR 200) COM is transmitting.
Connect to another COM’s TX Interlock input. TX INTERLOCK OUT will sink 20mA of current and
will output a voltage of 1V or less.
TX Interlock In is an active low input that desenses (protects) the COM receiver when another COM is
transmitting.
TX Interlock In is considered active if either the voltage to ground is ≤ 3.5 VDC or the resistance to ground
is ≤ 375

.
TX Interlock In is considered inactive if the voltage to ground is 6.5-33 VDC or the resistance to ground is
>100 k

.
4.11 Discrete Inputs
These discrete inputs are active low and are configurable.
Active-Low discrete inputs are considered active if either the voltage to ground is
≤ 3.5 VDC or the
resistance to ground is ≤ 375 W.
These inputs are considered inactive if the voltage to ground is 6.5-33 VDC or the resistance to ground is
>100 kW.
Pin Name
Pin I/O
PILOT PTT*
35 In
COPILOT PTT
* 15 In
*Indicates Active Low
Pin Name Pin I/O
TX INTERLOCK OUT 4 Out
TX INTERLOCK IN* 5 In
*Indicates Active Low
Pin Name Pin I/O
DISC 1* 2 In
DISC 2* 22 In
*Indicates Active Low