Comtech EF Data SMS-758 - Manual (Page 12)

Table of Contents SMS-758 Modem Protection Switch
viii MN/SMS758 Rev. 3
4.9 IF Switch..................................................................................................................................................... 4–47
4.9.1 Specifications ....................................................................................................................................... 4–47
4.9.2 Theory of Operation ............................................................................................................................. 4–47
4.10 Online Telemetry ..................................................................................................................................... 4–49
4.10.1 Specifications ..................................................................................................................................... 4–49
4.10.2 Theory of Operation ........................................................................................................................... 4–49
4.11 Power Supply ........................................................................................................................................... 4–51
4.11.1 Specifications ..................................................................................................................................... 4–51
CHAPTER 5. MAINTENANCE ................................................................................... 5–1
5.1 Fault Descriptions........................................................................................................................................ 5–1
5.1.1 Modulator Operation Fault ..................................................................................................................... 5–1
5.1.2 Demodulator Operation Fault................................................................................................................. 5–1
5.1.3 M:N Faults.............................................................................................................................................. 5–2
5.1.4 Battery Faults ......................................................................................................................................... 5–2
5.2 Fault Isolation .............................................................................................................................................. 5–3
5.2.1 Modulator Operation .............................................................................................................................. 5–3
5.2.2 Demodulator Operation .......................................................................................................................... 5–4
5.2.3 M:N Operation ....................................................................................................................................... 5–5
5.2.4 Battery .................................................................................................................................................... 5–6
5.3 Module Replacement ................................................................................................................................... 5–7
5.3.1 Power Supply ......................................................................................................................................... 5–7
5.3.2 IF Switch ................................................................................................................................................ 5–8
5.3.3 Switch Driver ......................................................................................................................................... 5–8
5.3.4 Address Decoder/Driver......................................................................................................................... 5–8
5.3.5 M&C ...................................................................................................................................................... 5–8
5.3.6 Online Telemetry.................................................................................................................................... 5–9
5.3.7 Interface Switches .................................................................................................................................. 5–9
5.4 Repacking for Shipment.............................................................................................................................. 5–9
5.4.1 Return Instructions ................................................................................................................................. 5–9
5.4.2 Repacking Instructions ........................................................................................................................... 5–9
APPENDIX A. REMOTE CONTROL OPERATION: MODEM SWITCH.................... A–1
A.1 General ........................................................................................................................................................A–1
A.2 Message Structure ......................................................................................................................................A–1
A.2.1 Start Character .......................................................................................................................................A–2
A.2.2 Device Address......................................................................................................................................A–2
A.2.3 Command/Responses.............................................................................................................................A–3
A.2.4 End Character ........................................................................................................................................A–3