L3 Communications FA2100 - Model Fa2100 Cvr System Theory of Operation; Theory of Operation

COMPONENT MAINTENANCE MANUAL
AVIATION RECORDERS
FA2100CVR
Page 30
Nov. 01/98
Description and Operation
23–70–04
6. THEORY OF OPERATION
The theory of operation provided for the Model FA2100CVR describes the function of the
recorder both at the system level, PWA level and software operational level. System level
theory of operation describes the general operation of the system as a whole. Refer to
the Model FA2100CVR System Block Diagram during the following discussion. The
theory of operation for each PWA describes the electrical circuitry of the major functional
groupings contained on the individual PWAs. The software level theory describes the
modes of operation of the recorder software.
A. MODEL FA2100 CVR SYSTEM THEORY OF OPERATION
The ARINC 557/757/757A, Model FA2100CVR consists of four subassemblies, the
Aircraft Interface Printed Wiring Assembly (PWA), the Audio Compressor PWA, the
Acquisition Processor PWA, and Crash Survivable Memory Unit (CSMU). The re-
corder interfaces with the aircraft’s cockpit recorder control unit and microphone
through the rear panel connector J1 and with the Ground Station Equipment through
the front panel GSE connector. The descriptions and block diagrams of these sub-
assemblies are provided in this section to support level two maintenance coverage
of this unit.
Aircraft
Interface
(AI)
Audio
Compressor
(AC)
J1
Acquisition
Processor
(AP)
Crash Surviv-
able
Memory Unit
Processor
(CSMU)
GSE –> PI
TDM/HSS
Rear Front
TDM
HSS
– Digitized Audio Storage
– CVR Control
– Fault Processing
– Logic Power Supply
– ADPCM Encoding
– GMT Merging
– Signal Conditioning
– Power Supply
Aircraft
Signals &
Power
Analog
Audio
Signals
Power
Signals
Figure 11.
FA2100 CVR Overall Function Block Diagram
May 21/1
3
Rev. 11 Page 30