Ross ACO-4400A, Руководство пользователя

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1–2 • Introduction ACO-4400A User Manual (Iss. 03)
Overview
The ACO-4400A is designed for high reliability Master Sync operations where two SRG-4400
units are provided as a fail-safe Primary and Backup pair. The ACO-4400A provides automatic
fail over to the wide range of SRG-4400 reference signals.
The ACO-4400A provides user-selection of reference sources. Automatic changeover may occur
upon fault detection in any active source.
The ACO-4400A is an in-line device without internal buffers. Switching for all channels is by
mechanical relay. The ACO-4400A also provides internal termination for unswitched BNC
inputs.
The ACO-4400A includes 12 channels in a 1U rack. Each BNC channel consists of a Primary
Input, a Backup Input, and an Output. All BNC channel relays switch in unison upon fault
detection in any active BNC channel, front-panel command, or remote command.
In conjunction with the BNC channels, there are a number of unmonitored secondary channels
available on Molex® connectors. All secondary connector channel relays switch in unison upon
fault detection in any active BNC channel, front-panel command, or remote command.
The ACO-4400A uses signal amplitude as the basis for error checking. You can configure each
BNC channel to check for a different type of input. There is a selection of predefined checking
levels relating to the various signals that are supported:
• No Measurement
• Color Black (no ancillary signals present, i.e. only Sync and Burst)
• Color Black + VITC (with one or some ancillary signals present)
• 600mV Tri Sync
• SD SDI - LOS
• HD SDI - LOS
• 3G SDI - LOS
• 1V 10MHz
• 1V Sub-carrier
• 1V AES
• 2V Pulses - LOS
• 4V Pulses - LOS
For the common signals, a fault is reported when the input signal level falls below a
predetermined ratio of the nominal peak value. Visual fault indications appear on the front-panel
display for signals from both the Primary and Backup SRG-4400s. These indications remain on
until cleared by the operator.
For other signals, a simple “Loss Of Signal” (LOS) detection is performed.
The signal reference amplitudes used for fault detection are programmed during factory
calibration. The ACO-4400A includes dual power supplies, which provide power supply failure
redundancy.