Comtech EF Data SDM-9000 Installation And Operation Manual page 14

Preface
5.5.2.2 ECL ........................................................................................................................................................... 5-20
5.5.2.3 MIL-STD-188 ........................................................................................................................................... 5-20
5.5.3 Theory of Operation ......................................................................................................................................... 5-21
5.5.3.1 Transmit Data Path.................................................................................................................................... 5-23
5.5.3.2 Receive Data Path ..................................................................................................................................... 5-24
5.5.3.3 Loopbacks ................................................................................................................................................. 5-26
5.5.3.3.1 Baseband Loopback ........................................................................................................................... 5-26
5.5.3.3.2 Interface Loopback ............................................................................................................................ 5-27
5.5.3.4 Engineering Service Channel (ESC) ......................................................................................................... 5-27
5.6 Backward Alarm Theory and Connections ......................................................................................................... 5-28
CHAPTER 6. MAINTENANCE......................................................................................... 6-1
6.1 System Checkout .................................................................................................................................................... 6-1
6.1.1 Interface ............................................................................................................................................................ 6-1
6.1.2 Modulator ......................................................................................................................................................... 6-3
6.1.3 Demodulator ..................................................................................................................................................... 6-8
6.1.4 Test Points ........................................................................................................................................................ 6-10
6.1.4.1 Interface PCB ............................................................................................................................................ 6-10
6.1.4.2 Modulator PCB ......................................................................................................................................... 6-11
6.1.4.3 Demodulator PCB ..................................................................................................................................... 6-12
6.2 Fault Isolation......................................................................................................................................................... 6-13
6.2.1 Guidelines......................................................................................................................................................... 6-13
6.2.2 System Faults/Alarms....................................................................................................................................... 6-14
6.2.2.1 Fault/Alarm Display and Description........................................................................................................ 6-18
6.2.2.2 Fault/Alarm Analysis ................................................................................................................................ 6-19
6.2.2.2.1 Modulator Faults ................................................................................................................................ 6-19
6.2.2.2.2 Demodulator Faults............................................................................................................................ 6-20
6.2.2.2.3 TX Interface Faults ............................................................................................................................ 6-22
6.2.2.2.4 RX Interface Faults ............................................................................................................................ 6-23
6.2.2.2.5 Common Equipment Faults................................................................................................................ 6-25
6.2.2.2.6 Backward Alarms............................................................................................................................... 6-26
6.3 Module Replacement ............................................................................................................................................. 6-27
6.4 Module Identification ............................................................................................................................................ 6-27
6.5 Repacking for Shipment ........................................................................................................................................ 6-27
APPENDIX A. OPTIONS .................................................................................................. A-1
A.1 Reed-Solomon Codec ............................................................................................................................................ A-1
A.1.1 Specifications................................................................................................................................................... A-2
A.1.2 Theory of Operation......................................................................................................................................... A-2
A.1.2.1 Reed-Solomon Encoder............................................................................................................................ A-2
A.1.2.2 Reed-Solomon Decoder............................................................................................................................ A-5
A.1.3 Installation ....................................................................................................................................................... A-7
A.1.3.1 Unpacking Instructions............................................................................................................................. A-7
A.1.3.2 Tools Required ......................................................................................................................................... A-7
A.1.3.3 Installation Procedure............................................................................................................................... A-8
A.2 Direct Broadcast Satellite ..................................................................................................................................... A-10
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SDM-9000 Satelite Modem
Rev. 4