EXFO FTB-800 Series for FTB-1 - Manual (Page 34)

Physical Interfaces and LEDs
24 FTB-700G/800 Series
EXT CLK
EXT CLK
The FTB-700G/800 Series provides one connector, labeled EXT CLK that
can be used either for input/output external clock DS1 (1.5M), E1 (2M),
2MHz, or 1PPS synchronization signal. 1PPS is available for Dual Test Set in
One-Way Latency measurement mode. The connector type is BNC for
coaxial 75-ohm cable connection. An adapter cable (BNC to Bantam) is
required for Bantam connection (not supplied).
LEDs

LASER red LED is on when the FTB-700G/800 Series is emitting an
optical laser signal.

LINK green LED is on when the link is up, off when the link is down,
and flashing when frames are transmitted and/or received.
C
AUTION
To prevent exceeding the maximum input power level please use an
attenuator when a loopback configuration is used.