Nortel Networks 553-3001-211 manual Clock rate converter

Page 826 of 894 NTRB21 DTI/PRI/DCH TMDI card

IMPORTANT!

Each MG 1000S that has a digital trunk must have a clock controller clocked to an external reference clock.

If an IP Expansion multi-cabinet system is equipped with digital trunk cards, it is mandatory that at least one trunk card is placed in the Main Option 11C cabinet. A cabinet that has a digital trunk must have a clock controller.

Note: Clocking slips can occur between MG 1000S systems that are clocked from different COs, if the COs are not synchronized. The slips can degrade voice quality.

Clock rate converter

The 1.5 Mb clock is generated by a Phase-Locked Loop (PLL). The PLL synchronizes the 1.5 Mb DS1 clock to the 2.56 Mb system clock through the common multiple of 8 kHz by using the main frame synchronization signal.

553-3001-211 Standard 2.00 September 2004