IRT Communications DMM-4880, Instruction Manual

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DMM ‐ 4880 & DMX ‐ 4880 Instruction Book Revision 0
www.irtelectronics.com Page 5 of 16 4880 ‐ DMM_4880 ‐ DMX_ib_Rev0.doc
IRT Eurocard
Type DMM ‐ 4880 & DMX ‐ 4880
4 STM ‐ 1 to STM ‐ 4
Multiplexer / De ‐ Multiplexer
General Description
The DMM
‐ 4880 and DMX ‐ 4880 are part of a family of network adapters for converting between STM ‐ 1 and STM ‐ 4
formats.
With the DMM
‐ 4880 up to four 155Mb/s STM ‐ 1 electrical signals can be multiplexed together and converted into
a single 622Mb/s STM ‐ 4 optical NRZ signal.
Inputs are automatically equalised for lengths of up to 200m of Belden 8281 or equivalent cable.
Front panel indications on the DMM
‐ 4880 multiplexer shows if valid STM ‐ 1 signals are present.
Optional STM
‐ 4 reference input for synchronizing to STM ‐ 4 network, if required.
The DMX
‐ 4880 separates the 622Mb/s STM ‐ 4 signal back into the original four 155Mb/s STM ‐ 1 signals.
Front panel indications on the DMX
‐ 4880 de ‐ multiplexer shows if valid encoded STM ‐ 1 signals are present.
SNMP (Simple Network Management Protocol) is available for monitoring and control when used in an IRT frame
fitted with SNMP capability.
The DMM
‐ 4880 and DMX ‐ 4880 are designed to fit IRT’s standard Eurocard frames and may be used alongside any
other of IRT’s analogue or digital Eurocards.
Standard features:
•
Up to 4 STM ‐ 1 electrical streams on one STM ‐ 4 link
•
Automatic Input equalisation > 200m
•
Recovers transmitted STM ‐ 1 signals with minimal user setup
•
Monitoring and control via SNMP
•
Eurocard format
DMM-4880 & DMX-4880 Block Diagram
DMM-4880 DMX-4880
Alarm O/P
SNMP
Alarm O/P
SNMP
NOTE: *
STM-4 Reference input optional
.
STM-1 (1) I/P 1
STM-1 (2) I/P 2
STM-1 (3) I/P 3
STM-1 (4) I/P 4
STM-4 Ref
*
Ref I/P
STM-4
Network
O/P I/P
O/P 1 STM-1 (1)
O/P 2 STM-1 (2)
O/P 3 STM-1 (3)
O/P 4 STM-1 (4)
IRT
Communications
www.irtcommunications.com