The DDA-3301 is a data distribution amplifier that
operates in accordance with the G.703 specification1.
The G.703 rate must be specified when ordering and
may be 8, 34 or 45 Mb/s.
The DDA-3301 incorporates a protection facility for
switching to signals from a standby module when a
fault is detected.
Three outputs are provided at the rear of the module
with an additional output for monitoring purposes on
the front panel. The primary output is controlled by
relays to provide a bypass signal from the input
during a power failure.
An Alarm Indication Signal (AIS) detected in the data
stream generates a changeover request for a
companion unit. |
Indicators are provided on the front panel for:
DC power
Data loss
AIS detect
Module in service
Module in standby
External alarm signals are also available on the rear
of the module.
Changeover-inhibit and changeover-request switches
are provided on the front panel for use where
modules are linked in pairs for redundancy.
For this configuration, a special double width rear
assembly (type ZDA-3301RH) is available to link the
signal and logic sections of two modules. |
