Coastcom D/I Mux III System, User Manual

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Chapter 1. System Overview and Modes of Operation
24
Clock Select
The clock select function provides T1 clock selection options for T1-1 and T1-2 as follows:
•
Recovered clock T1-1
•
Recovered clock T1-2
•
Internal Stratum IV (1.544 MHz) clock source
•
External clock with the backplane DB-9 Sync I/O connector
•
Slot 2 Synchronization source
Frequency Synthesizer
The frequency synthesizer produces a 1.544 MHz Stratum IV clock. It can synchronize an
external clock input that is 8 kHz or greater, and a multiple of 1600 Hz up to 1.544 MHz.
The external clock is from either the backplane Sync I/O, or the Slot 2 Synchronization
source; selection is under software control.
See Figure 1-11 for a detailed AMCU motherboard circuit flow block diagram.
Clock should only be present on
either/or, not both , unless sourced form
the same reference.
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