Optelecom 9482-DR, Инструкция по установке и эксплуатации

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Functional Description
The 9482DT transmitter accepts four composite video signals in NTSC or PAL format via four BNC video input
ports. The baseband video signals are each sampled at a 15 Mhz rate by an A-to-D converter operating with
nine bits of precision. The resulting digital signals are multiplexed and serialized along with the serial data
from the two data ports and the high-speed port and converted to an optical signal for transmission over the
fiber. The control and data signals from the receiver end arrive via an optical receiver operating at a different
wavelength on the same fiber. The optical signal is converted back into a serial bit stream and demultiplexed
into data signals for the two data ports, the duplex high-speed port, and for the “up-the-coax” control signals.
The “up-the-coax” control signals are synchronized with the incoming video signals for output on the input
BNC connectors.
The 9482DR receiver accepts the optical signal from the transmitter and demultiplexes it into serial bit
streams for the video and the data. The video stream signal is converted back into four video signals that
are output at the BNC connectors. The data stream is demultiplexed and routed to the two data ports and
the high-speed port. Data input to the two data ports and the high-speed port is multiplexed together with
the “up-the-coax” control data that is input from the video output BNCs, serialized, and converted to an
optical signal for transport to the transmitter on the second wavelength.
The high-speed port provides a duplex 15 MB synchronous RS422 port. The port may be used as a 4-wire 1.5
Mbps asynchronous RS422 port; however, its primary purpose is to support optional accessory cards.
Currently, the port supports the 9961-C/9961A-C and 9962-C/9962A-C Option Module Host cards, the 9971-C
High-Speed Port to 10 Mb Ethernet Card with data ports, and the 9973-C High-Speed Port to 10 Base T 4-Port
Ethernet Switch card. Contact the factory to determine if there are other accessory cards available that will
operate on high-speed ports. RJ45 Cat5 cable used to connect the High-Speed port may not exceed 1.3
meters (4 feet) in length.
The 9482D cards operate on 6VDC as supplied by the chassis into which they are installed.