Important Codes:
1200 The VFR code for any altitude in the US (Refer to ICAO standards elsewhere) 7000 The VFR code commonly used in Europe (Refer to ICAO standards)
7500 Hijack code (Aircraft is subject to unlawful interference)
7600 Loss of communications
7700 Emergency
7777 Military interceptor operations (Never squawk this code)
0000 Military use
Avoid selecting codes 0000, 7500, and all codes in the
trigger special indicators in automated facilities. An aircraft’s transponder code is used for ATC tracking purposes, therefore exercise care when making routine code changes!
Keys for Other GTX 328 Functions
IDENT Pressing the IDENT Key activates the Special Position Identifica- tion (SPI) Pulse for 18 seconds, identifying your transponder return from others on the air traffic controller’s screen. The word ‘IDENT’ will appear in the upper left corner of the display while the IDENT mode is active.
VFR Sets the transponder code to the
FUNC Changes the page shown on the right side of the display. Display data includes Pressure Altitude, Flight Time, Altitude Monitor, Count Up and Count Down timers. Also displays Outside Air Temperature, Density Altitude, Contrast, and Display (dependent upon installation configuration). START/STOP Starts and stops the Altitude Monitor, Count Up, Count Down and Flight timers.
CRSR Initiates starting time entry for the Count Down timer and cancels transponder code entry.
CLR Resets the Count Up, Count Down and Flight timers. Cancels the previous keypress during code selection and Count Down entry. Returns cursor to the fourth code digit within five seconds after entry.
8 Reduces Contrast and Display Brightness when the respective fields are displayed (dependent upon installation configuration) and enters the number eight into the Count Down timer.
9 Increases Contrast and Display Brightness when the respective fields are displayed (dependent upon installation configuration) and enters the number nine into the Count Down timer.