Juniper CTP Series Hardware Manual page 16

one port needs to be used for both interfaces. One port is of the HD-26 connector type, and the other is
of the RJ-45 connector type.
On the CLK port, differential clock signals are output on the pins 4 and 17 of the HD-26 connector. When
an EIA-530A DCE-F serial cable (CTP150-CBL-DB25-DCE-F) is connected to the CLK port, the TT pins
24 and 11 of the DB25 connector output clock signals. If you configure a 32 kHz reference output, an
RS-422 32 kHz clock signal is generated on the pins. Even if you disable the 32 kHz reference output and
configure an external clock reference, the module expects an RS-422 clock input (of the configured
frequency) on the same pins.
NOTE: The external clock reference port must be connected to any module that is in slot 0, the
left-most module slot on the chassis.
RELATED DOCUMENTATION
CTP150 Serial Interface Module | 7
CTP150 Multiservice Interface Module | 8
CTP150 T1/E1 Interface Module | 9
CTP150 Interface Module HD-26 Connector Cable Pinouts | 27
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