4006-dda.ib.rev1.doc
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10/09/2008
DDA-4006
270 Mb/s ASI/SDI 8 O/P
Non-Reclocking Distribution Amplifier
General Description
The DDA-4006 270 Mb/s serial digital video distribution amplifier provides the user with a single standard module
to cover a wide range of distribution and monitoring functions for ASI or SDI signals.
Due to the fact that standard loop through techniques used in the analogue domain are unsuitable to the digital
domain most digital equipment comes with no facility to route the input signal to other locations. As a result a DA is
required at almost every point in the digital chain.
Serial digital signals also suffer severe deterioration over relatively short cable distances. The DDA-4006 provides a
means of extending the working distances that can be achieved by equalising and re-transmitting the data mid route.
The DDA-4006 may also be used to provide input equalisation for devices not having this feature, as most
unequalised inputs will only support cable lengths of less than 20 metres.
Frequent re-clocking of serial digital signals can lead to serious increases in jitter with resultant data errors. The
DDA-4006 does not include re-clocking so as to minimise these errors, leaving re-clocking to be done by the
receiving device. For applications requiring reclocking the DDA-4007 should be used.
The rear assembly now includes a bypass relay, to switch the Input (SK1) to Output 1 (SK2) in the event of a power
failure, as standard.
An optional Simple Network Management Protocol (SNMP) plug-in module is available for remote monitoring of
input status and alarm state.
The DDA-4006 is designed to fit IRT’s Standard Eurocard frame as well as IRT’s 4000 series frame for use with
IRT’s SNMP system and may be used alongside any other of IRT’s analogue or digital Eurocards.
Features:
•
For use as buffer or distribution amplifier.
•
8 in-phase 270 Mb/s ASI or SDI reclocked outputs.
•
Automatic input equalisation to 250 metres.
•
Automatic output muting on no input.
•
Relay bypass on loss of power.
•
Front panel indicators provide monitoring of presence of input signal at 270 Mb/s.
•
Optional plug-in SNMP monitoring module.
O/P 2
O/P 3
O/P 4
O/P 5
O/P 6
O/P 7
O/P 8
OUTPUTS
EQUALISER
SIGNAL FAIL
DETECTION
INPUT
Relay RL 1 = Output Alarm
LINK
ALARM O/P
RL 1
BLOCK DIAGRAM DDA-4006 SIGNAL PATH
O/P 1
MON O/P
Relay Bypass on loss of power
RL1
SNMP
IRT
Communications
www.irtcommunications.com