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Page 128 of 188 NTD12 Dual-port DTI/PRI card description and installation
553-2901-200 Standard 11.00 August 1996
Figure 31 - Clock Controller primary and secondary tracking
Free run (non-tracking) mode
The clock synchronization of the Meridian 1 or Meridian SL-1 may operate
in free-run mode if:
— no loop is defined as the primary or secondary clock reference,
— the primary and secondary references are disabled, or
— the primary and secondary references are in local (near end) alarm
Clock
J2
DDP
primary
clock controller back-up
REF 1
Secondary
PRIMARY
Reference
DDP
SECONDARY
Reference
clocking
source
Primary
clocking
source
REF 2
REF 1
REF 2
primary
secondary
secondary
J1
J3
Controller
0
Clock
J2
J1
J3
Controller
1