SystemBase

The normal problem of how to provide communication circuits for a World Cup, this time held in Korea & Japan was made more difficult with the initial absents of ISDN in Korea. The Koreans had moved straight to ADSL, unfortunately not a suitable medium for broadcast audio circuits; I am please to say with perseverance ISDN was provided at the IBC.

The main service was to be via a fully redundant E1 data circuit provided by Wold International between London and Korea. This circuit would carry all the necessary communication and programme circuits to and from the ITV Sport technical facility housed in the IBC (international Broadcast Centre) in Seoul and ITV's studio in London. However, such an arrangement would mean all our communication "eggs" would be in one basket .

A total of 4 x 15khz and 14 x 3.7khz bi directional circuits, plus 4 x PABX extensions were provided between London and the Host Broadcaster's gateway facilities within the IBC in Seoul. These circuits carried the Commentary from each game plus the various feedback and mix minus facilities needed to control its integration into the final studio output the viewer receives on his TV at home.

The E1 data was fed via an Intraplex multiplexer into the X21 capability of Systembase C310xr Codec already in everyday use within the London Studio (TLS) lines area. Using the C310xr units also allowed the use of ISDN as a backup and provided other advantages. Firstly the ATPX algorithm is known and trusted and provides a minimum of delay, secondly the engineering staff were familiar with the operation of the units and thirdly the units could provide an automatic changeover to ISDN as a backup operation in case of failure of the E1 data circuit.

During the commissioning stages various tests were carried out to gauge the time taken for all circuits to be up and running following a total failure, this was found to be on average to be between 40 to 90sec per channel.

Due to the number of codecs (11 at each end) it was decided to display the status monitoring and control of each unit on to a single screen on the respective control desks. This was achieved by making use of the serial (RS232) port on each codec and some PC software produced by one of the TLS lines engineers (Bob Hardy).

I am pleased to say that the backup was not used in anger during the event, but did provide another level of security for the ITV Sport production.

Jon Pearce -Technical Producer ITV Sport
Terry Palmer -consultant

ABU ISDN Backup System

At the beginning of this year NTL Broadcast, as the main provider of transmission services for UK independent radio, embarked on a 18 month project to re-engineer the GWR Radio Group VHF and MF network. This required the provision of ISDN backup at all line fed sites where an ISDN connection could be achieved. We had originally planned on using a system supplied by KW Electronics, however, the sudden closure of the company meant that this could not happen.

Fortunately, Systembase agreed to design a new product based on our specific requirements, and within our timescales, called the ABU ISDN Backup System. We were very pleased by Systembase's response, as the entire system was designed and production units delivered for installation within 3 months.

The basic function of the ABU System is to independently monitor and provide automatic ISDN backup for existing analogue audio circuits. The key application is for the backup of Studio-to-Transmitter links maintaining programme continuity. Any point-to-point audio circuit can be backed up by the ABU System irrespective of the transmission method, allowing future upgrades from analogue lines to digital without having to replace the backup equipment.

As most systems require a third source to be made available should the studio output have failed completely, the ABU System offers an additional input for an auxiliary source. This can be either a CD/DAT player (for which a contact closure is provided), or a DAB feed where it exists. The latter has become an important option for NTL in recent times. Additional features include a remote management and re-configuration facility, and a comprehensive set of alarm outputs for diagnostic purposes.

The final product not only met our specification, but exceeded it in terms of both the technical and operational aspects. As a result of the success of the Systembase ABU System, it has subsequently been implemented by NTL in other projects as a general high quality ISDN backup solution.

Written by:- Jeff Bradshaw Project Manager NTL Broadcast Tel: +44 1924 508 045 Fax: +44 1924 508 059 e-mail: jeff.bradshaw@ntl.com

Talk Radio Re-Launches

UK Broadcaster "Talk Sport" have not only updated their image, but also their audio distribution network. A total of 13 additional C310xr codecs have been installed by BT Broadcast Services earlier this year.

BBC Music Live

BBC Music Live was Britain first ever twenty four hour radio and T.V music extravaganza, with continuous coverage from start to finish over the weekend (27th-29th May). The weekend was a great success as 60 outside broadcast units relayed the action to listeners in real time using amongst their array of technology, Systembase C400xr Stereo Audio Codecs.

With both BBC radio 2 and BBC radio 1 broadcasting acts from the event, it had a wide reaching spectrum of listeners from the elderly, to the young. And with BBC television extending the net of participants even further, the whole country experienced a musical medley of diverse acts ranging from dance artist Moby to orchestras reprising the classics.

Plans are already underway for a 'World Music Live', encapsulating the event's spirit by transmitting a world-wide all day and night music festival, made possible by the reliability and real time capabilities of Systembase codecs, as well as the BBC engineer's expertise.

European Championships 2000-Belgium/Holland

It's four years since the last European Championships took place in England, this time there will be two nations co-hosting the tournament. Potential disaster for all broadcasters awaits, as games are staged from one country to the next, and compatibility is the big question mark in everybody's mind.

Fortunately, there is a codec which can meet the needs (and does) of the European market, supremely suited for live broadcasts including commentary and real time interviews for the post-match analysis. The Systembase range of ISDN Stereo Audio Codecs meet all these needs of the broadcaster; and will be extensively used during the tournament this summer.

International broadcasters such as BskyB, BBC, BT, CCTV (Central China Television), Charter Broadcast and Talk Sport are already installing units out in the Netherlands and Belgium in anticipation of the big event, confident in the equipment's ability to always deliver reliability with no compromise on quality. So with the certainty of hearing every goal and cheer delivered by Systembase codecs this summer, all that's left to chance is the result.

BT Install C100xr for Talk Radio UK

The Systembase C100xr audio Codecs supplied to BT for the Talk Radio UK distribution network, incorporate the apt-X100 compression system, with it's inherently low and constant coding delays of less than 10ms, thus making the units ideally suited for live applications such as speech based radio. In addition, the C100xr Codec is not specifically designed for use over ISDN, since an ISDN Terminal Adapter (T.A.) is not built-in. Instead, the Codec has a standard X.21 network interface, enabling it to be readily used over various types of digital networks which include permanent digital data circuits (56Kbps up to 256Kbps), as in the case of Talk Radio UK, or over cable networks, satellite links and of course ISDN lines via an external TA.

The C100xr Codec is capable of providing full duplex audio links ranging from bandwidths of 7.5KHz Mono, suitable for speech application, up to 15.2KHz stereo, for FM radio applications such as Studio-To-Transmitter Links (STL's). As in most commercial installations, with Talk Radio UK being no exception, rack space is at a premium. On this particular aspect, the slim, 19-inch, 1U high, rackmount enclosure of the C100xr was a distinct advantage, allowing the efficient use of the available rack space. The LED bar meters with selectable audio source have also proved to be valuable operational feature, making programme monitoring of the transmitted and received audio at the studio end, a quick and simple task.

Following almost three years of continuous operation at 24 hours per day, the Systembase C100xr Codecs have maintained an excellent reliability record. This has helped to endorse BT's confidence in the ability of the units to operate trouble-free throughout the 8 year license period awarded to Talk Radio UK.

RTL Build ATM Distribution Network

The world's first radio programme distribution network using ATM (Asynchronous Transfer Mode) technology, with ISDN back-up, has recently gone on-air in Belgium. Bel-RTL is a popular commercial radio station launched in September 1991, catering to the French speaking population of Belgium. Based in Brussels, they are closely linked with CLT-UFA in Luxembourg and the Belgian television branch of RTL (RTL-TVI).

Bel-RTL have a total of 15 FM transmitters, 13 of which are connected with leased lines and 2 are for re-broadcasting. In 1998 Belgacom (Belgium PTT) announced that they were going to be withdrawing the delivering of radio quality analogue leased line. Maintenance of the existing analogue lines would also be reduced, resulting in a progressive decrease in the quality of service. PTT's across Europe have taken similar decision in the past few years forcing broadcast customers to migrate to new digital services. Like many radio stations, Bel-RTL use MPEG encoding to produce their programming. Both news and commercials are MPEG encoded and stored on computer disk ready for play out. Hence particular attention had to be taken when deciding what type of audio codecs could be used in the distribution network to avoid the problems of cascade coding. The key component of the new Bel-RTL ATM network is thirty Systembase C310xr audio codecs which provide the high quality, real-time audio feeds to the FM transmitters. The C310xr are also responsible for the ISDN backup on detection of ATM network errors, and incorporate a comprehensive bit error rate test to verify error free operation of ATM network for restoration. Following a period of extensive evaluations of over 20 different manufacturers codecs, the Systembase C310xr audio codec was selected for a number of key reasons;
Output audio quality was excellent Good stereo image No problems with MPEG cascading Not sensitive to minor errors on the line X.21 Restore after Backup never failed Not sensitive to mains power supply problems Automatically monoised inputs on ISDN backup Analogue and digital interfaces provided as standard 1U rack enclosure with low power consumption Never requires power-on reset Availability of an additional 9600bps data channel.
The ISDN backup facility is particularly useful if Belgacom has a loss of connection or when an ATM update is required. After more than 6 months of rigorous trials, Bel-RTL have been very pleased with the operation of the Systembase C310xr codecs.

Systembase Heralds In The New Millennium

Systembase Codecs are to be used to transmit the sound that everyone was listening for on New Years Eve, the bell of Big Ben in London, heralding the dawn of the New Millennium. The New Millennium Experience Company (NMEC) has installed Systembase C400xr codecs immediately beneath the clock room at the Big Ben tower. The live sound of Big Ben will then be transmitted to the Millennium Broadcast Centre within the Millennium Dome, Greenwich, signalling the start of the Year 2000.

The high quality audio signal will be transmitted in stereo using two ISDN lines (4 x 64kbps). If one of the ISDN lines fails, the C400xr codecs have been configured to automatically drop down to a mono service using the remaining ISDN line.

The C400xr security features have been utilised to ensure that link integrity is maintained at all times, preventing accidental dial up access by other users. Systembase C400xr Codecs were chosen by the NMEC for two important reasons; firstly, they feature the shortest audio-to-audio transfer time, (less than 10ms), and secondly, the ability of Systembase codecs to accurately encode the complex harmonic structure of sounds such as Big Ben without any audible artefacts.

Systembase is first for Digital One

	NTL have now successfully launched the first phase of their Digital Radio network, Digital One, using Systembase Digital Audio Codecs. NTL will use a mixture of C310xr and C400xr Digital Audio Codecs to complete the other phases of the project which will eventually cover the entire UK from a central hub in Croydon.

The Systembase codecs were chosen by NTL after exhaustive testing against several other codec makes. NTL made their choice based on codec performance, reliability and the ability of the C400xr to give full stereo backup across ISDN.