Ericsson LBI-39224 manual

LBI-39224

3.Slave to external 1.544 MHz - Redundant Clock Circuits generated by the Clock Board synchronized to 1 (or 2 with redundancy) external clock source. Any CEC/IMC can be synchronized to the timing output from a T1/E1 multiplexer, microwave radio, fiber network, etc. Connect the external timing source to both Clock Boards in the CEC/IMC for redundancy. This mode is established by setting the Clock Board DIP switches to "Slave to Ext. 1544 kHz" and all T1/E1 Interface Cards' Slave Clock option to "NONE."

4.Slave to external 2.048 MHz (E1 mode only) - Redundant Clock Circuits generated by the Clock Board synchronized to 1 (or 2 with redundancy) external clock source. Any CEC/IMC can be synchronized to the timing output from a T1/E1 multiplexer, microwave radio, fiber network, etc. Connect the external timing source to both Clock Boards in the CEC/IMC for redundancy. This mode is established by setting the Clock Board DIP switches to "Slave to 2048 kHz" and all T1/E1 Interface Cards' Slave Clock option to "NONE."

The following configuration guidelines must be followed for network synchronization:

1.One node in the system must be the MASTER source of network timing. The CEC/IMC will support a primary and redundant (or alternate) MASTER sources of timing as indicated above.

2.A MASTER node can be defined as a site, a Jessica, a T1/E1 link, or a CEC/IMC.

3.All leased T1/E1 facilities from the telephone company are frequency locked by the phone company. If there are any phone company T1/E1 connections, one of the connections must be the MASTER source of timing. Any other phone company connections may be the redundant MASTER source of timing. Phone company T1/E1 connections include leased lines for sites/multinode and T1/E1 connections through an MD110 (Jessica).

4.Any nodes using analog interfaces (including analog connections from an MD110 to the phone company) may be disregarded for synchronization purposes.

5.If a node is not a MASTER timing node, it must be slaved to the T1/E1 link going towards the MASTER node.

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