Endace DAG 4.2S, Руководство пользователя

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EDM01-02: DAG 4.2S Card User Guide
©2005 17 Version 7: May 2006
Description
, continued
If it is necessary to connect the transmit port of the DAG 4.2S card to
other equipment, it is necessary to enable the transmit laser. The laser
normally used is eye safe, but is disabled as a precaution as it is not
normally needed.
The laser radiation is in the invisible infrared part of the spectrum. When
the laser is turned on, the red laser warning LED will be lit.
In a test-bench situation where two DAG cards are connected directly to
each other, one card must be designated the SONET clock master. This
can only be done on cards fitted with 77MHz SONET master clock
oscillator crystal.
In normal use the DAG card should be the SONET clock slave, deriving
its signals from the received network stream.