No Longer Available - For Reference Purposes Only
     

DDT-4220 & DDR-4225:   270Mb/s / ASI / SDI 4 Channel MUX Fibre Link.

FEATURES:

      270 Mb/s type signals, such as ASI and SDI, capability.
      Automatic cable equalisation for up to 200m on each input.
      Maximum optical path loss of 32dB.
      External urgent and non-urgent alarms for system monitoring.
      Optional plug-in SNMP monitoring module.

Brochure  

User Manual  

APPLICATIONS:

      Multichannel digital with data on a single fibre.
      Upgrade capacity of existing fibre.
      Maintain timing between related signals by ensuring same path transmission delay.

GENERAL:

The DDT-4220 accepts up to four 270 Mb/s input signals which may be ASI, SDI or a mixture of each type. The signals need not be phase or frequency synchronous.

The signals are time division multiplexed into a single 1.302 Gb/s stream and transmitted via single mode fibre to the DDR-4225 receiver, which performs the reverse operation and restores correct 270 Mb/s timing.

In addition to the four 270 Mb/s channels, a single RS422 channel is included for transmission of auxiliary data at rates of up to 9600 baud.

The DDT-4220/DDR-4225 optical system is primarily designed for use with a 9/125?m single mode fibre and will allow an optical path loss from 4dB up to 32dB.

An optional Simple Network Management Protocol (SNMP) plug-in module is available for remote monitoring of input and output status and alarm states.

The DDT-4220 transmitter comes available with a choice of standard 1310nm laser (order code DDT 4220/1300) or a DFB 1550nm laser (order code DDT 4220/1550). Other wavelengths are available on request. The DDR-4225 receiver is the same regardless of transmitter wavelength.

The modules are designed to fit IRT's standard Eurocard frames 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.


TECHNICAL SPECIFICATIONS:

DDT-4220:
Inputs:
Type
4 x 270 Mb/s ±100 ppm, 0.8 Vp-p./ASI/SDI.
Equalisation
Automatic for up to 250 m of Belden 8281 or equivalent cable.
Format
Synchronous or asynchronous.
Connectors
 BNC 75 Ω.

RS-422:
Type
1 x 9600 baud, synchronous or asynchronous.
Connectors
HE 14/8 / matches DN 9.

Outputs:
Type
1 x 1.302 Gb/s optical (wavelength dependent on unit ordered).
Power level
0 dBm (1 mW) ± 1 dB.
Connector
SC/PC.

Alarms:
Urgent
N/C relay for loss of power, TX lock error or LASER fail.
Non-urgent
N/C relay if no channels are present.

DDR-4225:
Input:
Type†
1 x 1.302 Gb/s optical.
Power level*
-4 dBm to > - 32 dBm.
Connector
SC/PC.

Outputs:
Type
4 x 270 Mb/s ±100 ppm, 0.8 Vp-p./ASI/SDI.
Format
synchronous or asynchronous.
Connectors
BNC 75 Ω.

RS-422:
Type
1 x 9600 baud, synchronous or asynchronous.
Connectors
HE 14/8 / matches DN 9.

Alarms:
Urgent
N/C relay for loss of power, RX lock error or optical input fail.
Non-urgent
N/C relay if no channels are present.

Optical:
Optical path loss*
4 dB to 32 dB.
Optical fibre
Designed for use with 9/125 µm single mode fibre.
Optical wavelength
1310nm or 1550nm. See ordering information below. Other wavelengths available on request.

Power Requirements:
Voltage
28 Vac CT (14-0-14) or ±16 Vdc.
Power consumption
DDT-4220 <10 VA, DDR-4225 <12.5 VA.

Other:
Temperature range
0 - 50°C ambient.
Ordering information
DDT-4220/1300 standard 1310 nm model; DDT-4220/1550 DFB 1550nm model.
Mechanical
Suitable for mounting in IRT 19" rack chassis with all connections at the rear.
Finish:             Front panel
Grey background, black lettering & red IRT logo.
                       Rear assembly
Detachable silk-screened PCB with direct mount connectors to Eurocard and external signals.
Dimensions
6 HP x 3 U x 220 mm IRT Eurocard.
Supplied accessories
Rear connector assembly including matching connector for switcher control.
Optional accessories
SMU-4000 SNMP plug in module for use with 4000 series frame fitted with SNMP "Agent".
                       NOTE: *
Optical attenuator must be used for DDR-4225 when optical path loss is less than 4 dB.
                                  †
Single mode tail on detector.



                     



Due to our policy of continuing development, these specifications are subject to change without notice.