Garmin GTN 725 Installation Manual page 66

4.3.9.2 AUDIO INHIBIT IN*
The AUDIO INHIBIT IN discrete input may be used to suppress TAWS and touch screen feedback audio
from the GTN.
4.3.9.3 TAWS INHIBIT IN*
The TAWS INHIBIT IN discrete input, when toggled momentarily low, may be used to inhibit TAWS
alerts from the GTN.
4.3.9.4 AIR/GROUND*
The AIR/GROUND discrete input may be used to control the air/ground status of the GTN.
4.3.9.5 CDI SOURCE SELECT* (GTN 750 only)
The CDI SOURCE SELECT discrete input may be used to toggle between display of GPS and
VOR/LOC/Glideslope information on the MAIN external CDI/HSI. A momentary low on this pin
performs the same function as pressing the 'CDI' button on the GTN display.
4.3.9.6 DEMO MODE SELECT*
The DEMO MODE SELECT discrete input may be used to select Demo Mode on the GTN. When this
pin is connected to ground during power up, the GTN starts up in Demo Mode. Demo Mode allows the
GTN to simulate reception of GPS satellite signals.
Do not connect DEMO MODE SELECT in an aircraft installation.
Demo Mode can also be accessed by holding down the D
4.3.9.7 SYSTEM ID PROGRAM*
The System ID PROGRAM discrete input is used to identify the #2 unit in an installation with more than
one GTN. This input must be strapped to ground on the second GTN.
SYSTEM ID PROGRAM*
Open
Ground
4.3.9.8 SYNCHRO VALID INPUT
There are two SYNCHRO VALID INPUTs; one is active-high and the other is active-low. Unless one of
the two input is active, the GTN considers the synchro heading input to be invalid.
Page 4-18
Rev. A
CAUTION
NOTE
button during power-up.
GTN Installation
GTN #1 or single-GTN installation
GTN #2
GTN 725/750 TSO Installation Manual
190-01007-02