Agilent Technologies auroraSonata, User Manual

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aurora
Sonata
Hand Held ISDN Tester—User Guide
4-16 427869
Warning: High voltages
If the word ‘over’ appears after the voltage measurement for a
U interface, refer to Chapter 9 section 1 for the maximum
voltage that can be applied safely. A reading above this level
means that a dangerous voltage may be present. Disconnect
aurora
Sonata from the line, observing all safety precautions.
Checking Layer 1
Layer 1 (the ‘physical’ layer of the OSI 7-layer model) is
responsible for the electrical, mechanical and interface aspects
of transmitted data. For calls to be possible, Layer 1 needs to
be active—i.e. available for passing Layer 2 frames.
Tip
You will find more information about the OSI 7-layer model
in the
Glossary and the Introduction to ISDN .
In Simulation mode, you can tell whether Layer 1 is active by
checking the
Line A LED.
Off
means that Layer 1 is not
active,
flashing green
means that Layer 1 is activating and
steady green
means that Layer 1 is fully active.
Activation of Layer 1
The point at which Layer 1 activates is determined by when
aurora
Sonata
establishes the Layer 2 link—i.e. the
Mode
setting
in the
Layer 2
menu. When this is
Permanent
, Layer 1
activates as soon as you connect to the line. When it is
Automatic
, Layer 1 activates when you make or receive a call.
For details of Layer 2 setup, see Setting up the Layer 2
protocol in Chapter 3 section 1.
Layer 1 activation may take up to 35 seconds when connecting
to a CorNet-T switch. This is a feature of the ISPBX which
may vary according to the load.