In a minimal installation, the GDL-88 provides the required ADS-B Out functionality with a standalone set of annunciators and control switches installed in the cockpit. When a GDL-88 is installed without interface to an external display, some ADS-B In functionality is still retained. A traffic annunciation light is installed in the cockpit for CSA (Conflict Situational Awareness) alerts and aural alerts are provided for these threat aircraft, to include directionality from the ownship and range.