Sandel ST3400, Installation Manual

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The configuration is performed in the Maintenance Menu pages given in the
Setup Procedures section of this manual.
3.7 Audio Panel
The Audio output is required for Class A and Class B compliance. The ST3400
has provisions for low level audio output located on J1-30 and simultaneous direct
speaker audio on J1-15 for units with mod-A. The LL audio output must interface
to the un-switched audio input of the aircraft audio system.
The audio output produces the GPWS “whoop-whoop” as well as human voice
callouts. The LL audio output is the ‘master level’ and the ‘speaker audio’ has a
separate adjustment on the installation maintenance page to trim the speaker
level relative to the headphone level. If after adjustment the available speaker
audio level is insufficient, turn up the master audio level at the ST3400 and make
a corresponding reduction in the LL audio level at the headphone amplifier.
The overall level is based on the nominal and maximum audio level
configuration. The maximum audio level is a maximum of four (4) times the
nominal audio level. The audio level automatically ranges from the Nominal
Audio Level to the Maximum Audio Level as the aircraft airspeed increases.
3.8 GPS/FMS
A Global Positioning System (GPS) or Flight Management System (FMS) input is
required for both Class A and Class B compliance.
Note: This system must be GPS-based system and meet TSO-C129a or C-145
requirements. GPS is used for lateral positional and to display flight plan
information. In certain installations it may also be used for vertical position.
The ST3400 has provisions for one or two simultaneous GPS ARINC 429
receiver ports. The primary port is located on J-1 and the optional secondary port
is located on J-2. The receiver ports are configurable in the Maintenance Menu
pages for High or Low speed ARINC. A list of supported Labels is given in an
Appendix of this manual.
3.9 Radar Altimeter
The Radar Altimeter input is required for Class A compliance and is
recommended for Class B.
The ST3400 has provisions for one Radar Altimeter input. The primary input is
located on J-1. (With the exception of the RA FAIL input, see below). Radar
Altimeter input may be from an ARINC 429 or DC Analog sources. The Radar
Altimeter input is used to obtain Height Above Terrain for GPWS alerting. The
ST3400 will support 2000 ft Radar Altimeters such as the Collins ALT-50A in
either Class A or Class B installations. The radar altimeter may be connected
using its analog outputs or through an existing analog-to-429 converter.
The ST3400 will accept analog ALT50/55, ARINC 552, KRA10 and other analog
type inputs.
82002-IM-L ST3400 INSTALLATION MANUAL
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