Northern Airborne Technology 802 - Manual (Page 21)

802-009 Switch Panel
SM802 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 4 Page 3-1
Section 3 Operation
3.1 Introduction
Information in this section consists of functional and operational procedures for the 802-009 Switch Panel.
3.2 General Information
The 802-009 Switch Panel shown in Figure 1 is designed to control a single Model 700-xxx Digital Audio
Control Amplifier. It also provides microphone audio switching and keying operations for four radio
transmitters in addition to features such as antenna switching unit control, marker (MKR) receiver
sensitivity control and public address (PA) amplifier control. The 802-009 Switch Panel continuously
reads the status of its own audio control switches and volume control potentiometers and compiles this
information into the form of a digital signal. The digital signal is sent to the Model 700 from the switch
panel in RS422 serial format via a twisted, shielded wire pair. The Model 700 receives, demultiplexes and
converts this digital signal into useful audio control information.
The 802-009 Switch Panel is capable of digitally controlling all Model 700 amplifier functions. These
include the 12 receiver input switches and individual volume controls, the four sidetone input switches
and sidetone volume control, the three microphone input switches, the interphone switches and volume
control, the cockpit speaker switch and volume control, the headphone volume control and the NAV/ADF
Voice/Ident filter switching functions. Refer to the Model 700 Digital Audio Control Amplifier Equipment
Manual (NAT Seattle Document 700-16) for more specific information on Model 700 functions.
Figure 1: 802-009 Switch Panel
ENG-FORM: 806-0112.DOT
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