INSTALLATION MANUAL
89000007
Page 2-12
15 Nov 2013
© Honeywell International Inc. Do not copy without express permission of Honeywell.
2.6.9 Altitude Alerter Output
The KT 74 includes an altitude monitor function that can alert the pilot to
altitude deviations in cruise flight. The altitude alerter output, on the 12-way
secondary connector, is switched to ground when the altitude deviation is
detected and can be connected to a visual or aural warning device to alert
the pilot. The output is an open collector transistor, and can sink up to 1 AMP
DC. The switched voltage should not exceed 60 volts.
2.6.10 GPS Position Input
The GPS position input is required to support ADS-B functionality. The GPS
position input is an RS232 input to the transponder. The ADS-B features are
optional – no GPS is required for normal Mode S elementary surveillance.
The GPS input is on the 24 way primary connector.
The KT 74 GPS input can recognize the following protocols:
Aviation
Format
NMEA
0183
NexNav/FreeFlt
Garmin
ADS-B
Trig
ADS-B
BK GPS Xpress.
The interface speed can be selected between 1,200, 2,400, 4,800, 9,600,
19,200, 38,400, 57,600 and 115,200 bps.
Some of the protocols listed above may not contain all the required data for a
compliant ADS-B message, depending on the intended airspace regulations.
For further information refer to Section 1.26 (ADS-B Compliance) of this
manual.
2.6.11 TIS-A Traffic Output
The TIS-A traffic output supports the display of uplinked TIS-A messages. It
is provided on both an RS232 output on the 24-way primary connector and
an ARINC 429 output on the 12-way secondary connector. The KT 74 RS232
TIS-A output can drive the Trig proprietary traffic protocol, and can also
support the format used by certain Garmin handheld displays including the
495, 496, 695 and 696.
The KT 74 ARINC TIS-A output can drive a number of common traffic
displays, including Garmin and BendixKing multifunction displays.
NOTE:
TIS-A is a Mode S uplink service that is provided by some US approach
radars. TIS-A coverage is limited to the coverage areas of those radars.
There is no TIS-A provision outside the U.S.A.
