Megahertz builds OB truck for Kuwait TV

Kuwait TV took delivery of a High Definition OB truck this month. Digital Studio gets an exclusive look into the OB vehicle, designed and constructed by Megahertz Broadcast Systems, and reports on the technology used.

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By  Vijaya Cherian Published  December 27, 2004

I|~|OBtruck1.jpg|~|Kuwait TV's new HD OB truck|~|In October 2004, a huge white truck rolled into Megahertz Broadcast Systems’ workshops in Cambridgeshire, UK for the start of a transformation process that was to last four months. At 13.5 metres long and with one side capable of expanding 1.3 metres to give the truck an overall width of 3.8 metres, its dimensions were impressive. Yet inside, it was little more than an air-conditioned shell. On looking at it, one would never have guessed that this massive vehicle would soon become a mobile television studio, equipped to handle High Definition (HD) broadcasting or that it was destined to travel to different parts of the Middle East as part of Kuwait Television’s (KTV) outside broadcast (OB) fleet. KTV, which covers politics, news and current affairs, operates three networks and one satellite channel. The state broadcaster’s decision to build a new OB truck has been a long time in the making. A new vehicle was originally planned for the GCC sports tournament in 2002, but was delayed for ‘a multitude of reasons’, according to Salah Al Siddiqi, director of KTV studios and OB. However, technological advances in broadcasting and KTV’s need to expand its OB fleet eventually got the project the green light. “We already have three analogue OB vehicles in our fleet,” says Siddiqi. “The new truck falls within KTV’s overall plan to renovate and empower its capacity to cover sports and national events. It will be equipped to handle HD broadcasting, making it the first HD vehicle in the Middle East,” he adds. The first company to work on the truck was A. Smith Gt Bentley Ltd (ASGB), a UK-based coachbuilder that has been constructing OB vehicles for the last 25 years. ASGB began with a flatbed, three-axle chassis and custom-built the whole coach to the client’s specifications. This meant incorporating a hydraulically-driven expanding side so that when the vehicle was in use, an entire sidewall could be extended to create additional room for the broadcast engineering staff. The company was also responsible for installing the air conditioning and power supplies in the vehicle. Racks to house the equipment and furniture were also specially built and installed and the truck’s roof was strengthened so that KTV staff could use it as a camera platform when the vehicle was out in the field. “Every vehicle we have built has been designed entirely to customer specification,” says Simon Hare, managing director of ASGB. Building this coach included ensuring that the vehicle was equipped with the correct level of thermal and acoustic insulation. Additionally, electrical installations including multi-supply power distribution to supply systems racks, power sockets, lighting, air conditioning and other equipment were also incorporated in-house. ||**||II|~|obtruck2.jpg|~|KTV’s OB truck is equipped with Sony’s HD cameras, SD and HD routers and SD/HD vision mixers, a Studer Vista 7 audio desk as well as several TV monitors and a full range of outboard equipment.|~|After ASGB finished work on it, the truck was taken to OB specialist and systems integrator, Megahertz Broadcast Systems to install the broadcast equipment. “For this particular project, we worked very closely with our Kuwaiti partner EEMC to help specify the equipment for the vehicle and ensure that the project was completed on time and within budget,” says Frances Jarvis, who heads Megahertz. “We have always been aware of the requirement to consider the latest technology and, being an independent company, we could easily integrate the customer’s preferred suppliers in its system,” he adds. Having worked with these two companies in the past on several projects, including the refurbishment of KTV’s Master Control Centre (MCC), the state broadcaster was comfortable assigning this project to them as well. The MCC project involved the installation of serial digital video and digital audio central routing systems to serve production studios, continuity studios, edit areas and news centres. “We have built a good working relationship with the two companies,” says Siddiqi. “Megahertz and EEMC offered KTV the best advice on what systems and technologies to use,” he adds. Owing to the fact that this was a significantly high-budget project and also looking to support HD, equipment had to be chosen carefully. “This OB vehicle is one of two planned by KTV and is the kind of project you don’t invest in every year. For this reason, we had to ensure that the equipment we chose was capable of future expansion. This is why we have decided to make the truck HD. KTV is not broadcasting HD now, but plans are being formulated to do this in the future,” explains Siddiqi. The equipment list includes seven Sony HDC-950 HD cameras that work over fibre. Megahertz also supplied 64x64 standard definition (SD) and 64x64 HD Sony routers, a Sony MVS-8000A SD/HD vision mixer and a Studer Vista 7 audio desk. This, along with television monitors and a full range of outboard equipment, was installed into the truck in such a way that no cables were damaged when the expanding side was retracted, claims Jarvis. “We chose Sony because its HD solutions were more innovative in this instance,” he says. “Preparing for a future that incorporates HD broadcasting allows KTV to provide modern technological solutions to its customers,” he adds. The van is also equipped with a Studer Vista 7 digital audio production console, specified with 30 faders and 24 mics. The Studer Vista 7, known for its Vistonics operating concept, was preferred because it allows intuitive operation of its powerful processing algorithms. ||**||III|~||~||~|Steve Burgess, technical director of Megahertz, adds that equipping the truck for HD broadcasting meant specifying cables, connectors and patchbay panels that were all capable of handling a higher bandwidth signal. “Traditionally, the infrastructure of an installation has been designed to cope with the maximum data rate of 270Mbps for SD digital video signals. In the case of HDTV, we are dealing with a data rate of 1.5Gbps, with a third harmonic at 2.25GHz. SMPTE 292E states a required bandwidth for the interconnections of 2.4GHz. Furthermore, insertion loss at HDTV frequencies is significantly greater and care has to be taken to keep this below 20dB,” he explains. “Normally, we would aim for a headroom of 6dB allowing a loss of only 14dB. Finally, in the days of analogue, character impedance of the interconnections was virtually ignored, with integrators happily mixing 75 and 50 ohm components. With the advent of SDV at 270Mbps, care had to be taken to ensure all components were truly 75 ohm. In the case of HDTV, we have to be even more careful that we are seeing a purely resistive 75 ohms with the minimum of reactance, in order to avoid reflections on the cables,” he adds. For the KTV project, Megahertz chose Belden 1694A cable and BES Electronics patch panels. BNC connectors were chosen to ensure that they were capable of minimum insertion loss and 75 ohm impedance up to 3GHz. Although KTV isn’t currently broadcasting in HD, having an HD OB truck means that it can produce and record programming at a higher bandwidth and store that so it is there and ready to use when they need it. In the meantime, Megahertz has installed converters that allow KTV to broadcast in SD until they make the switch to HD. Integrating the equipment and testing took nearly four months. Once it was completed, the truck’s livery was added to give it KTV’s own branding. “This was a complex project because it involved such high specification equipment,” says Jarvis from Megahertz. “However, we are delighted with the result and are excited to have been involved in the building of the first HD OB vehicle for KTV. We are now working on a large HD vehicle for another customer and anticipate that, with the technological changes that are taking place in the world of broadcasting, we will be asked to build many more.” ||**||

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