Station Timing - General DataComm SpectraComm 553 Installation & Operation Manua

Timing Options

Station Timing

When the SC553 is optioned for station timing, it times data at its DS-1 network interface by means
of a 1.544 Mbps timing signal supplied from the Telco central office on a separate circuit. The
station clock signal is input to the SC553 at the lower RJ48 jack located at the rear of the
SpectraComm/UAS shelf on Zone1.(Refer to Chapter 2, Installation and Setup ). The timing
signals are transferred through that jack using a standard EIA RS-422 interface. See
SpectraComm/UAS Shelf
Lower RJ48 jack
at Zone 1
Cascade Equipment
Figure D-6
076R155-000
Issue 7
SC553 CSU/DSU
Station
Clock
Interface
Interface
to
Backplane
Data
Highways
Cascade
Interface
Station Timing
SpectraComm 553 Fractional T1 DSU
Installation and Operation Manual
Timing Option Descriptions
Network Transmit Timing Source
Internal
Station
Shelf
Cascade
Network
Interface
Figure D-6.
Receive
Transmit
D-9