5.
POST INSTALLATION CONFIGURATION AND CHECKOUT PROCEDURE
5.1
OPERATION
The coverage you can expect from the GTX 330 is limited to line of sight. Low altitude or
antenna shielding by the aircraft itself may result in reduced range. Range can be improved
by climbing to a higher altitude. It may be possible to minimize antenna shielding by
locating the antenna where dead spots are only noticed during abnormal flight attitudes.
5.1.1 Function Selector Switches
The function selection switches are:
• OFF Powers off the GTX 330. Pressing the STBY, ON or ALT key powers on the transponder
displaying the last active identification code.
• STBY Selects the standby mode. When in standby mode, the transponder will not reply to any
interrogations.
• ON Selects Mode A and Mode S. In this mode, the transponder replies to Mode A, Mode C and Mode
S interrogations, as indicated by the Reply Symbol ("
information.
• ALT Selects Mode A, Mode C and Mode S. In ALT mode, the transponder replies to identification,
altitude and Mode S interrogations as indicated by the Reply Symbol ("
interrogations include the standard pressure altitude received from an external altitude source,
which is not adjusted for barometric pressure. The ALT mode may be selected in aircraft not
equipped with an optional altitude encoder; however, the reply signal will not include altitude
information.
GTX 330 Installation Manual
190-00207-02
Figure 5-1. GTX 330 Front Panel
The GTX 330 should be turned off before starting aircraft engine(s).
NOTE
NOTE
®
"), but the replies do not include altitude
®
"). Replies to altitude
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