Timer Operation
To operate the Flight Timer:
1)Press the FUNC key until FLIGHT TIME is displayed.
2)If the GTX 330 is configured with Automated Airborne Determination, the timer begins automatically when the unit senses that the aircraft has become airborne. The timer may be reset to zero at every take off, continue accumulating time at take off, or may be controlled manually.
3)If desired, press START/STOP to pause or restart the timer.
4)Press CLR to reset the timer to zero.
5)If the timer is configured to start automatically it will stop when the Automated Airborne Determination senses that the aircraft is on the ground.
To operate the Count Up timer:
1)Press the FUNC key until COUNT UP is displayed.
2)If necessary, press CLR to reset the Count Up timer to zero.
3)Press START/STOP to begin count up.
4)Press START/STOP again to pause the timer.
5)Press CLR to reset the timer to zero.
To operate the Count Down timer:
1)Press the FUNC key until COUNT DOWN is displayed.
2)Press CRSR and use the 0 - 9 keys to set the initial time. All digits must be entered (use the 0 key to enter leading zeros).
3)Press START/STOP to begin count down.
4)Press START/STOP again to pause the timer.
5)When the Count Down timer expires, the COUNT DOWN banner is replaced with a flashing EXPIRED, the message “Timer Expired” is heard, and the time begins counting up.
6)Press CLR to reset the timer to the initial time value.
Automatic ALT/GND Mode Switching
If the GTX 330 is configured for Automated Airborne Determination, normal operation begins when take off is sensed. When the aircraft is on the ground the screen automatically displays GND. The transponder does not respond to ATCRBS interrogations when GND is annunciated. When a delay time is set (dependent upon installation configuration), the GTX 330 waits a specified length of time after landing before changing to GND mode.
Failure Annunciation
If the unit detects an internal failure, the screen displays FAIL. When FAIL is annunciated no transponder data is transmitted.