Garmin GTS 825 Pilots Guide - Page 7

The GTS 8XX Series provides for expanded audio messaging in an ATC-like verbal format: "Traffic. One o'clock. High (or Low or Same Altitude). Two miles." If surveillance bearing information is not available on the intruder, "Traffic, No Bearing" is called out. Bearing may be derived from either the top or bottom directional antenna depending upon which antenna hears the response. A directional antenna is used to derive bearing to the intruder aircraft, which is displayed with relative altitude to own aircraft. Top antenna transmitted interrogations are directional, reducing the number of transponders that receive the interrogation thus reducing potential garble on the 1090 MHz band. Note: GTS 8XX is used throughout this manual to refer to the GTS 800, 820, or 850 products. When a feature is unique to the GTS 800, 820, or 850 it will be specifically referenced as such. Product GTS 800 GTS 820 GTS 850 Traffic Advisory System (TAS) X X Traffic Alert and Collision Avoidance System X (TCAS I) LRU X X X GPA 65 PA/LNA X X 1090 ES ADS-B Receiver X X X Transmit Power (Watts) 40 250 250 Top-Mounted Garmin-Approved Directional X X X Antenna Optional Bottom-Mounted Garmin-Approved X X X Directional or Omnidirectional Antenna Table 2 GTS 8XX Series Family Product Description The GTS 8XX Series does not contain a display, but transmits traffic data to a Garmin or third party multi-function display that is capable of displaying traffic data. More information is located in the installation manual. The GTS 8XX Series supplies data to a traffic display to indicate the presence and location of intruder aircraft. The information provides the crew with the intruder's range, bearing, and, for altitude reporting intruders, relative altitude and vertical trend. TCAS I symbology as defined in the FAA Advisory Circular entitled "Airworthiness 190-00587-02 Rev. A Garmin GTS 8XX Series Traffic Advisory System 3