Garmin GDL 88 manual Interfaces, Audio Panel, Altitude Source, TAS and TCAS Traffic Systems

6.2Interfaces

6.2.1Audio Panel

Traffic alert audio output is interfaced to a required audio panel with a compatible unswitched unmuted audio input.

6.2.2Altitude Source

The GDL 88 requires the use of an ownship pressure altitude for transmission of required ADS-B Out data values and to calculate the vertical separation and vertical closure from target aircraft.

6.2.3TAS and TCAS Traffic Systems

The GDL 88 will interface with the GTS 800, 820, and 850, Skywatch, Skywatch HP, and Ryan TCAD.

6.2.4Heading Source (optional)

The GDL 88 can optionally use heading for the purpose of correlating ADS-B traffic and traffic received from the external traffic system. HSDB and ARINC 429 digital heading is provided to the GDL 88 from any compatible magnetic heading source. Multiple heading sources may be connected to the GDL 88.

6.2.5GPS Position Source

The GDL 88 uses the ownship GPS position for creation of the ADS-B Out messages as well as the receipt and tracking of ADS-B In targets. The GDL 88 without the internal GPS WAAS requires at least one compatible GPS position source be installed, while the GDL 88 with the internal GPS WAAS engine may optionally be interfaced with compatible sources.

6.2.6Radar Altimeter (Optional)

The GDL 88 can optionally be interfaced with a radar altimeter to drive the sensitivity level of the Conflict Situational Awareness (CSA) application.

6.2.7Traffic Mute (Optional)

The GDL 88 can optionally interface with a pilot controlled switch to acknowledge an active Conflict Situational Awareness (CSA) alert and mute the associated aural alert. This momentary switch only mutes the current CSAs and does not act as an inhibit for future CSA aural annunciations.

6-2 GDL 88 ADS-B Transceiver Pilot’s Guide 190-01122-03 Rev. A