Opengear MUX-6258-A-261, Руководство пользователя

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3–6 • User Controls MUX-6258-A Series User Manual (Iss. 04)
Operation Notes
This section provides additional information for operating the card such as audio proc amp
controls, the minimum delay, embedding PCM versus Non-PCM signals, and ancillary data
processing.
Audio Proc Amp Controls
The card includes Processing Amplifiers (Proc Amps) for the audio inputs on the card. Note that
these features are not available when using the card-edge controls.
Proc Amp adjustments are applied in the following order:
1. Sum — This option enables both channels to carry the average of the two input
channels (A+B/2). When the input is summed, the original signals are no longer
available for output. This option only operates with AES input pairs.
2. Delay — This option enables you to adjust the delay of the audio channel. If you have
enabled the Delay Lock feature, changing the delay value for one channel automatically
changes the value for the other channel.
3. Gain — This option provides a +/- 20dB gain range in 1dB increments. If you have
enabled the Gain Lock feature, changing the gain value for one channel automatically
changes the value for the other channel.
4. Invert — This option enables you to invert the polarity of the audio signal for the
selected channel.
Minimum Delay Overview
The line buffer stores incoming video in relation to the incoming video clock timing. The video
data is then read out in relation to the reference timing. This allows the input video to be switched
between sources that may not be perfectly timed without timing glitches. Video source timing
must remain within the buffer window to properly switch between sources.
Table 3.3 provides
information on the buffer window available depending on how the Minimum Delay option is
configured in DashBoard.
Embedding PCM Signals
The card can embed PCM audio from two sources: the AES input or from the embedded audio of
the source video. Processing also includes embedding channel status data as per
Table 6.2 .
Table 3.3 Minimum Delay Option
If the option is... Format Minimum Delay Maximum Delay
Disabled
SD 1/4 line 1/2 line
HD 1/4 line 1/2 line
Enabled
SD 1/8 line 1/4 line
HD 1/16 line 1/8 line