Ross ASI-310, Руководство пользователя

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ASI-310 User Guide (v5.0) Before You Begin • 11
Before You Begin
The ASI-310 accepts a DVB-ASI input containing an MPEG 2 Transport Stream, and produces a SMPTE 310M
Transport Stream output at one of two frequencies: 19.392659 or 38.785317Mbps. It also simultaneously accepts a
310M Transport Stream at either of the standard frequencies and produces a DVB-ASI signal.
Overview
The ASI-310 provides a number of innovative tools to simplify your work-flow. For example:
• It allows user setup of the 310M input and output rates to either of the two available frequencies.
• It has an accurate on-board temperature-compensated crystal oscillator that generates a free-running output
frequency which meets the specified tolerance of ± 2.8ppm.
• For applications requiring even tighter frequency tolerance, or to ensure frequency coherence with house sync,
the user can provide a 310 input and set the ASI-310 to lock its output bit rate to it.
• The ASI-310 accepts a Transport Stream having a rate much higher or lower than the selected output 310 rate,
provided that the net input rate (input rate not including null packets) is less than or equal to the selected 310 rate.
If the average input rate is too low, the ASI-310 adds null packets as needed to maintain the output rate; if the
input rate is too high, it deletes null packets as needed.
• The ASI-310 provides selectable PCR re-stamping to correct timing errors caused by the insertion or deletion of
null packets to achieve the desired 310M output bit rate.
• The included 310-to-ASI converter allows independent simultaneous conversions in both directions.
• The combination of a second 310M output and the 310-to-ASI converter allows in-service monitoring of the
310M output with ASI-based equipment such as the Ross Video TSM-100.
• Error conditions such as loss of input, or a net input rate exceeding the output rate, are reported through the GUI
and can be assigned to GPI/O outputs for connection to an external alarm or monitoring system.
• The ASI-310 tolerates any single occurrence of an invalid sync character before declaring loss of sync. Upon loss
of sync, caused for example by asynchronous switching of ASI signals, it recovers sync rapidly.
Features
The following features make the ASI-310 the solution of choice for converting MPEG Transport Streams in
DVB-ASI format to SMPTE 310M as commonly used in ATSC systems:
• ASI input and two 310 outputs on 75ohm BNC jacks located on the rear module.
• 310M input and ASI output on 75ohm BNC jacks located on the rear module
• Independently selectable 310M input and output rates: 19.392659 or 38.785317Mbps
• Selectable clock source: on-board temperature-compensated crystal oscillator or 310M input
• Rate conversion and PCR re-stamping
• Cards are hot-pluggable for ease of configuration and maintenance.
• Compatible with the openGear frame’s SNMP option, allowing monitoring with third-party SNMP software
systems
• Fits openGear frames