Post Installation Configuration & Checkout
190-01499-02
GTX 3X5 Transponder TSO Installation Manual
Rev. 9
Page 6-13
Discrete Out
Table 6-8 Discrete Outputs
[1] Available in system software v2.10 or later.
Figure 6-12 Discrete Out Page
Function
Pin Selection
Description
Notes
ALT ALERT
Off
All discrete outputs on P3251 or P3252
When this discrete is grounded, it
indicates a deviation from the preset
altitude setting.
FAIL 1
Off
P3251-17
Failure of transponder causes discrete
to ground.
FAIL 2
Off
All discrete outputs on P3251 or P3252
Failure of transponder causes discrete
to open.
RPLY ACTV
Off
All discrete outputs on P3251 or P3252
Discrete grounds when transponder
sends replies to interrogations.
EQUIP STS
Off
All discrete outputs on P3251 or P3252
If the unit needs service soon, this
discrete will switch between open and
ground for the first 30 seconds after
power up. If after 30 seconds, there is
no detection of ADS-B In/Out failures
the discrete opens. The discrete will
ground if any ADS-B In/Out failures are
detected after 30 seconds.
TRFC STBY
Off
All discrete outputs on P3251 or P3252
Commands TAS/TCAS standby/
operate. Discrete output operation
automatically sets through TAS/TCAS
input configuration. GTX 345 only.
TRFC TEST
Off
All discrete outputs on P3251 or P3252
Commands TAS/TCAS into test mode.
GTX 345 only.
TRFC ALRT
Off
All discrete outputs on P3251 or P3252
When a traffic alert is active, this
discrete will ground. GTX 345 only.
TCAD SL
Off
All discrete outputs on P3251 or P3252
Supports automatic control and
integration with Ryan TCAD and
Avidyne TAS600 Series traffic systems.
GTX 345 only.
XPDR ACTV
Off
All discretes outputs on P3251
Discrete grounds when transponder is
not in standby.
[1]
ADS-B OUT
Off
All discrete outputs on P3251 or P3252
Discrete grounds when ADS-B Out is
on and the unit does not have a valid
GPS position.
[1]