DashBoard Enabled

IRT-6638-DDT & IRT-6638-DDR: 8-Channel 3G/HD/SD-SDI/ASI Fibre Optic Link

IRT-6638-DDT & IRT-6638-DDR Home Page, PDF Brochure

The IRT-6638-DDT and IRT-6638-DDR is an 8-Channel 3G/HD/SD-SDI/ASI channel optical fibre link for point to point transmission using single mode fibre.


  • Transports up to 8 independent 3G-SDI, HD-SDI, SD-SDI or ASI signal rates on a single fibre via an on-board CWDM optical combiner.
  • Path lengths up to 27 dB1 optical path loss using 9/125μm single mode fibre.
  • Transmitter (Tx) and receiver (Rx) can be used separately with 8 independent single channel fibre Rx and Tx cards via an external CWDM optical combiner.
  • DashBoard and SNMP software monitoring and control.

IRT-6638-DDT & IRT-6638-DDR Block Diagram

The IRT-6638-DDT and IRT-6638-DDR are 8 channel transmit and receive modules designed principally for use as eight serial data fibre optic transmission links on a single fibre for 3G SDI, HD SDI or SD SDI applications conforming to SMPTE standards 424M, 292M and 259M-C using 9/125 μm single mode fibre. This enables the use of space saving fibre optic cable for reliable transmission of digital video signals over lengths greater than can be achieved with coaxial cable.

In addition, the links may be used for ASI transport streams for use with MPEG compressed video streams or other 270 Mb/s type data.

The receivers use APD detectors with signal conditioning and reclocking circuits. The data rates are automatically set to match the 3G SDI, HD SDI or SD SDI/ASI rates dependent on the actual input data rates to the transmitters. A PIN detector version is also available for short run applications.

The transmitter and receiver modules are compatible with IRT’s single channel fibre cards for use as eight independent fibre paths starting from or coming to a single location when used in conjunction with an external 8 channel CWDM optical combiner/de-combiner.

A DIP switch selectable “keep link alive” signal is available to maintain optical link operation when no electrical input is present.

The IRT-6638-DDT and IRT-6638-DDR are designed to fit the openGear® standard 2RU frames which allow a mixture of cards from various manufacturers to be mounted within the same frame.

DashBoard control software is available as a free download.

NOTE: 1 – 24dB path loss at 3G. Typically >27dB at HD and SD. Fitted with APD detector.

Product by:

IRT Communications IRT specialises in the design, development and manufacture of Digital and Analogue Video / Audio Broadcast and communications products including MPEG, ASI, DVB, AES/EBU, G.703, Distribution Amplifiers (DAs), HDTV and Fibre (Fiber) Optic devices used in telecommunication (ITU) and broadcast centres. Visit irtcommunications.com…