Garmin GTX 23 ES, Installation Manual

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GTX 23 Installation Manual Page 4-3
190-00906-01 Revision A
4.2 Discrete Functions
4.2.1 Discrete Outputs
External suppression should be connected if a DME or TCAS is installed in the aircraft avionics system.
The GTX 23 suppression I/O pulses may not be compatible with all models of DME or TCAS. Known
incompatible DME units include the Bendix/King KN 62, KN 64 and KNS 80. These models have an
output-only suppression port and can be damaged by the GTX 23 mutual suppression output. In this case,
do not connect the GTX 23’s suppression pin to the incompatible unit’s suppression pin; however, do
connect the GTX 23’s suppression pin to any other compatible unit’s suppression pin.
4.2.2 Discrete Inputs
*
INACTIVE: 10
≤
Vin
≤
33Vdc or Rin
≥
100k Ω
ACTIVE: Vin
≤
1.9Vdc with
≥
75 uA sink current, or Rin
≤
375 Ω
Sink current is internally limited to 200 uA max for a grounded input
EXTERNAL IDENT SELECT (remote IDENT) is a momentary input. When grounded, it activates the
IDENT pulse for 18 seconds in Mode A replies.
EXTERNAL STANDBY SELECT (remote STANDBY) is not a momentary input. When EXTERNAL
STANDBY SELECT is grounded, the GTX 23 operates in standby mode. In this mode, the transponder
will not squitter or reply to interrogations.
TIS CONNECT SELECT is a momentary input. When grounded, it toggles whether TIS is in standby or
operating.
Pin Name Connector Pin I/O
EXTERNAL SUPPRESSION I/O (TXP/DME) P2301 31 I/O
Pin Name Connector Pin I/O
EXTERNAL IDENT SELECT* P2301 12 In
EXTERNAL STANDBY SELECT* P2301 13 In
TIS CONNECT SELECT P2301 46 In