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Operating in a tapeless world

WETA-DT had more than modest goals for the $8.5 million digital revamp of its origination and transmission facility for SDTV, HDTV and FM broadcast: create a completely tapeless operation for both programs and interstitials, full automation, and dynamic monitoring of all channels coming out of the facility. And that was just the beginning.

WETA-DT engineers engaged in a lengthy debate over the drawbacks of traditional videotape and the practicality of chucking it, given today's level of video server development. In the end, tape was relegated to the dustbin.

"Our goal was to future-proof the facility," says vice president of technology Lewis Zager. "We feel that the future architecture for broadcast origination facilities is server-based, not tape-based. So that is the architecture we adopted."

With the assistance of systems integrator Communications Engineering Inc., the WETA-DT engineering team designed and rebuilt the plant, which was completed in November. The entire facility, including the TV and radio facilities and supporting infrastructure, occupies approximately 12,000 square feet.

Currently, the facility is transmitting NTSC channel 26 and HDTV/SDTV channel 27 using its new digital infrastructure. But the wiring and gear is in place to add additional channels. "They could easily go from two to six additional standard-definition channels, and even multiple HD channels, should it be desired," says Lawrence Brody, president of CEI.

To support the anticipated large volume of SD and HD programming, possibly from new program streams or services for broadcast clients, weta specified both 270-Mb/sec and 1.5-Gb/sec SDI video, along with AES/EBU audio routing and distribution. Two Grass Valley Group Profile servers, each with about 720 Gb, or about 70 hours of storage, provide ingest and playout of program content from network satellite feeds or external videotape. The video servers are also set up for redundancy to protect the on-air broadcast.

HDTV programming currently originates from Panasonic HD D5 and Sony HDCAM VTRs, which play back to a Grass Valley HD master-control switcher. The HDTV signal is then fed to a Harris/Lucent FlexiCoder ATSC encoding system with a PSIP+ generator. A Sencore AT951R 19.39-Mb/s disk server is used for replay of pre-encoded HD streams.

Besides servers, WETA-DT engineers wanted to keep a significant amount of material in nearline storage using a StorageTek robotic data tape library with 17.3 terabytes, or approximately 3,500 hours, of storage. A direct Fibre Channel link to the servers allows for rapid, simultaneous transfer of programming-as fast as four hour-long programs in 14 minutes-with all four StorageTek tape drives activated, according to Brody.

The audio infrastructure includes a Tektronix AES/ EBU synchronous routing system. It is shared with radio station WETA(FM) (90.9), although both have separate routers.

Engineers also wanted an optimized monitoring system that could be easily reconfigured depending on how many channels were being broadcast at any given time, whether two or eight. Rather than use fixed monitors, the solution was a custom monitor wall and operator's console. Everything that appears on-screen is user-definable, from the size of the monitor to the aspect ratio. The monitor wall is an amalgamation of large displays by Sony (one 42-inch plasma display panel, three 50-inch LCD rear projection displays, and three 34-inch widescreen HD monitors), along with smaller monitors (9- and 14-inch) from Sony and Ikegami and flat-panel computer monitors. They are all integrated with a Miranda multi-image display system.

The graphics system incorporates a Chyron Maxine! graphics system and an HD Duet character generator. A source ID system is used to help operators-one to four, depending on program schedule and complexity-keep track of all the program sources.

WETA-DT is one of the first users of Louth's Global Media Transfer (GMT) technology, according to Brody. Louth GMT can find program or interstitial information existing anywhere on the system and, if it's needed, transfer it to the server and get it ready for playout.

One thing that is not digital is weta-dt's nearby analog production facility, located about a city block away. This production studio is linked to the new facility using a weta-owned 60-strand fiber-optic bundle. Signals from the analog production studio can be called up transparently via the control system in the new facility.

New digital studios and production sites are being considered but may have to wait. "The primary mission was to be able to operate a tapeless environment, and that's pretty much what we have accomplished," Zager says.

Tape is primarily used for overflow. And tapes are sometimes pulled from existing archives or brought in from the outside. But ultimately, everything is fed into the servers. What actually goes on air in SDTV is almost never from tape.

Zager recently asked one of his staffers what he thought of a broadcast facility that's so automated that there is no tape to physically handle and load. "He said he's happy to be here, but he's bored," Zager says. "We will find something for him to do. But in the meantime, I am happy for somebody to be bored, because it means things are running as designed."