Multitech MT64DSU Owner's Manual page 54

MT64DSU Owner's Manual
EXTERNAL CLOCKING APPLICATION
This application is similar to the Local Area Data Set application
except for the timing option setting. In the example below, the DTE
connector of the T1 mux is connected to the DTE connector of the
MultiDSU64K. Here, the MultiDSU64K must receive timing
information from the T1 mux. The MultiDSU64K is set for external
timing in this type of application. At the DTE end, DDS timing is
selected, providing normal clocking to the DTE.
The figure below shows a typical External Clocking application.
Figure B-4. External Clocking Application
ANALOG OFF-NET EXTENSION APPLICATION
In this application, the MultiDSU64K is used with conventional
analog modems and lines to complete DDS circuits in an area where
DDS is not available, or where the customer requires an extension
of the DDS circuit for a special application.
In applications using the MultiDSU64K for an off-net extension, one
MultiDSU64K may be set for External Timing and the other set for
DDS Timing; however, in this application, the clock (timing) being
supplied must be accurate to +/-0.008% of the enabled data
transmission rate.
The Elastic Store option is used in off-net extension applications
with analog modems to compensate for small timing phase drifts
that typically occur in such applications. A "cross-over" cable is
required to connect the MultiDSU64K DCE connector to the analog
modem in this application (see Appendix C).
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