Garmin GTS 855 - Manual (Page 7)

3 190-00587-02 Rev. A Garmin GTS 8XX Series Traffic Advisory System
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
(TCAS I) X
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
Antenna X X X
Optional Bottom-Mounted Garmin-Approved
Directional or Omnidirectional Antenna X X X
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