Excellence in Broadcast

Magic TBR Tunnel Break-In Rebroadcast System

Brand: AVT

The MAGIC TBR Tunnel Break-in Rebroadcast system is a DAB+ repeater and at the same time a Voice Break-in system in a 19“ housing with only 2U, realized on a signal-processor based hardware platform.

To cover all possible encoder scenarios for replacing all audio programs within an ensemble during an emergency announcement, three encoders per ensemble are integrated. The entire multiplex is completely replicated and replaced frame-synchronously.
This technique was developed by the company Ingenieurbüro Mulka and applied for a European patent. From the view of a DAB radio a continuous signal is received in terms of data rate, sampling frequency, error protection, but also CIF Counter, time etc.

In this way it is guaranteed that the DAB receiver does not loose the synchronisation or even re-scans the DAB band.

If a driver hears another medium (e. g. CD) the receiver can be automatically switched to DAB mode by means of a suitable alarm signalling (if this is supported by the receiver).

The integrated flash memory allows the storage of prepared slideshows and dynamic labels as well as periodic repeating information announcements. These announcements can be activated automatically via a scheduler.
In parallel, PAD data in the form of a Slideshow and/or as Dynamic Label can be transmitted so that the respective information can also be presented visually.

The complete Ensemble can be monitored via a Monitoring Decoder.

In the standard operation mode the system functions a classic repeater. The DAB Ensemble is received by an antenna outside the tunnel, is filtered digitally and processed. Via the tunnel antenna the signal is broadcasted again.

A GPS signal is not required for this function. However, inputs are available for future extensions.

During the repeater operation the received Ensemble is analysed permanently to always have the current Multiplex Configuration Information (MCI) available – even after reconfigurations.


  • DAB Receiver/Demodulator
  • DAB Modulator/Repeater
  • An emergency announcement replaces all DAB/DAB+ programs at the same time
  • Integrated Monitoring Decoder
  • No GPS for synchronisation necessary
  • Flash Memory for announcements and PAD (Dynamic Label and Slideshow)
  • Support of EWF
  • 2 x analogue Audio inputs/outputs
  • 4 x digital Audio inputs/outputs
  • Headphones output
  • 2 x Ethernet interfaces (for control, monitoring, SNMP and optional VoIP)
  • Programmable GPIOs (8 x TTL, 8 x Relays)
  • Clock inputs for future extensions

Ensemble Module Upgrade
The standard system has a demodulator/modulator module for one Ensemble. If required the system can be equipped with a further module for a second Ensemble. Both Ensembles are completely independent from each other – a separate break-in is also possible.

Break-In via Telephone
As not all tunnels are permanently staffed, it is possible to use VoIP telephony as an alternative to conventional analogue and digital audio interfaces. This can be used, for example, to connect to the tunnel from any mobile phone. For security reasons, VoIP break-in is protected by a PIN code or an access number list.