AT&T 7500 series Network Router User Manual


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SYNCHRONIZATION OF DIGITAL FACILITIES B-25
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SECONDARY (BACKUP) FREQUENCY REFERENCE
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PRIMARY FREQUENCY REFERENCE
DIGITAL TRANSMISSION FACILITY
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Figure B-17. Excessive Cascading
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SECONDARY (BACKUP) FREQUENCY REFERENCE
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PRIMARY FREQUENCY REFERENCE
DIGITAL TRANSMISSION FACILITY
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Figure B-18. Minimized Cascading
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