Sonifex RB-FS82 Audio Failover Switcher, 8 Main I/O, 2 Standby I/O

Sonifex RB-FS82 Audio Failover Switcher, 8 Main I/O, 2 Standby I/O

The RB-FS82 8 + 2 audio failover switcher is a vital component in numerous crucial broadcast chains and telecommunications industries.

The device features RS232 connections (both inputs and outputs), stereo analog audio, AES/EBU digital audio, and eight primaries plus two backup connections. It may be set over Ethernet for two primary operating applications:

• For "Standbys to outputs," the process of moving program inputs to a backup destination in case the primary destination fails. For audio via IP, E1, or other bearer networks, this would typically involve audio encoders at a program distribution head end, with "N" x programs feeding "N" x encoders. In the event of an encoder failure, the audio intended for that encoder is diverted to a backup encoder, guaranteeing the uninterrupted flow of audio via the network.

• In case of a source failure, switching program sources—including standby sources—to destinations (also known as "standbys to inputs"). This would usually need audio decoders at a transmission site that are fed by "N" x transmitters and "N" x programs. The audio from a backup decoder or another audio source, like an MP3 player, overrides the signal flow to the transmitter in the event of a decoder failure, guaranteeing broadcast continuity.

The RB-FS82 supports any configuration of up to 8 main program signal paths (N = 8) and there are 2 standby program signal paths, in either mode of operation. Each programming path simultaneously switches analog L/R audio, AES/EBU digital audio, and RS232 data. Each of these signals is wired on D-Type connectors on the rear panel.

All signal paths are passive and therefore completely transparent utilizing relay-based switching. This has the benefit of a “straight wire” topology during normal (alarm-free) operation and also during any power outage to the device. An additional benefit of the passive signal path is AES/EBU bit transparency allowing throughput of AES/EBU AC3 Dolby E (TM) signals.

To ensure the passive nature of the device, switching is determined by alarm (General Purpose) inputs, with this alarm signaling, in turn, being normally provided by the encoder or decoders (or other devices) at the site. Recognizing the mission-critical nature of the system, a high grade of relay is used in the RB-FS82.

The passive design ensures continuity of audio in the event of any power outage. However, the RB-FS82 also includes dual redundant power supplies (85V-264V AC with a 12V 1A DC backup as standard). The RB-FS82-DC model accepts two DC power inputs (24 - 48V DC) via locking 2.5mm pin power connectors and both power supplies are monitored by the unit. This means that if either power supply fails, the other is ready to take over. In the extremely unlikely event that both fail, the unit’s passive signal path ensures a straight wire connection for all 8 program feeds (analog, AES/EBU & RS232). This is essential for applications such as installation at transmitter sites, where a power failure to the unit will not prevent the audio input signal from being output to each of the supported 8 transmitters.

A row of LEDs on the front panel confirms the unit status, with each program path indicated as being in alarm with either Standby 1 or Standby 2 programs confirmed as actively overriding the failed signal. Alarm LEDs on the front panel are also indicated for power supply 1 failure and power supply 2 failure and these are mirrored by the device’s own General Purpose Outputs facilitating easy interfacing of the device with the addition of a summary alarm status GPO.

By monitoring and acting on active low GPI Alarms for each signal path the unit can switch each main path between: Through, Standby 1, Standby 2, or Silence. The unit will always attempt to route a Standby path when a Main path alarm is detected and if both Standby paths are already in use, then one of the two remaining options (Through, Silence) will be used. The unit can be configured to either Automatically restore a Main ‘through’ path or wait for a Manual button press.

In the event of alarm clearing, the unit will automatically revert to normal operation, but a manual reversion mode is also provided, allowing for engineering investigation without the unit ‘hunting’ between different signal paths. Two buttons on the front panel, RESTORE 1 and RESTORE 2, allow manual restoration of the previously failed signal paths, away from Standby 1 and Standby 2 respectively.

To facilitate integration with site management systems the RB-FS82 supports SNMP V1 and is configured by a simple web-based GUI. All relevant information regarding input/output status, alarms, and power supplies is available via SNMP GET requests to the unit. Traps can also be generated for most of the actions that can occur, including power supply failure and input GPI alarms, etc. Contact Sonifex for further information if you have a particular requirement that isn’t catered for by the RB-FS82 as standard.

Key Features

• Relay-based switching.
• Dual DC, or AC, power supplies (select when ordering).
• Encoder site (Set via IP): 8 stereo program inputs, 8 + 2 stereo program outputs where each program input/Output carries: analogue L/R, stereo AES/EBU & RS232.
• Encoder site: Each program output has an alarm detect GP input.
• Decoder Site (Set via IP): 8 +2 stereo program inputs, 8 program outputs where each program input carries: analog L/R, stereo AES/EBU & RS232.
• Decoder Site: Each program input has an alarm to detect GP input.
• AES/EBU transparent (for Dolby E transport).
• Passive throughput in the event of a power outage.
• GPO output for signaling RB-FS82 alarm conditions: PSU 1/2 fail, Standby 1/2 active, Summary Alarm.
• Automatic or Manual reversion modes.
• LED indicators on the front panel.
• IP control, including Web GUI and SNMP.