KXAS-TV5, an NBC-owned and -operated station serving the Dallas-Fort Worth metro area, recently completed a major renovation of its television studios. KXAS is the oldest TV station in the Southwest and posed unique renovation problems--the building that houses it has been designated an historic landmark by the state of Texas, and its studio had not been upgraded in 30 years.

The original configuration of the studio, which opened in 1948, resembled a motion picture soundstage more than a TV studio. The architectural plans for the building were adapted from plans for a high school, with the gym space becoming the studios. The last attempt to modernize the studio 30 years ago left KXAS with huge Kliegl SCR dimmer packs in the basement, a plug-in patch panel in the corner of the main studio, and a two-wire ungrounded electrical system.

Renovation of the Fort Worth facility included completely new wiring in the main studios, installation of Rosco/Entertainment Technology dimming and control systems, and a new lighting grid system. Design and implementation of the renovation was by William Merrill Lighting Associates (WMLA) of Arlington, TX, with TPS Inc. of Atlanta handling the sale of the equipment. The electrical contractor on the project was Reese & Associates Electrical Co. Inc. of Crowley, TX.

As the systems designer for WMLA, I had to address several unique issues in developing the renovation specifications and plans. The station produces 6-8 hours of news programming daily in the studio, as well as weekly sports shows, public affairs programming, and other shows. Understandably, station management wanted minimal studio downtime for the renovation. Also, the news set could not be dismantled or moved to allow work on the grid and electrical systems overhead.

The existing grid was woefully inadequate for the news and production needs of the station. Given the necessity for a complete rewiring of the studios and major structural work to upgrade the grid with the large news set remaining in place, a traditional approach to the project would have required taking the main studio down for a month or more. I decided to use Rosco/ET IPS distributed dimming to solve the problems, and the renovation was accomplished with only one week of studio downtime.

By working mostly on weekends, Reese & Associates was able to install a new electrical system and wiring conduits along the two catwalks which flank the main studio, with zero studio downtime. This new electrical system completely bypassed the old wiring and dimmers. Along the conduit runs, junction boxes were installed to provide forty 3-phase/ 20A outlets to power the IPS dimmers, along with 14 DMX outputs, fed by two Rosco/ET DA8 DMX distro amps, to distribute the DMX signal from the Pentium PC-based Rosco/ET Horizon Gold control system. Three-phase twistlock connectors on SO cable were installed at the junction boxes and left coiled on the catwalks. The DMX outputs were also on cable runs and left coiled on the catwalks.

Station personnel worked between newscasts prior to the start date to remove the drop ceiling system that had been installed above the studio years before. This exposed the original grid, which had been welded to the building superstructure. Lights in the production end of the studio were removed in advance. In a previous remodeling, a partial lower grid, inadequate for current needs, had been suspended from the original piping below the drop ceiling on a 10'x12' (3x4m) pattern.

On a Saturday morning in January, with a temporary newsdesk set up in the station's Fort Worth newsroom, Reese's electricians cut the power to the antiquated electrical system, energized the new system, and began demolition of the old Kliegl dimmers and patch panel. Under the direction of KXAS lighting director Libby Altwegg, station personnel removed the lighting over the news set while WMLA personnel began work on the grid at the production end of the room.

Between each of the existing lower grid pipes, WMLA installed new grid pipes hung from the original upper grid using piping and hardware supplied by Channel One Lighting Systems of Tulsa, OK. They then connected the two grid structures together, resulting in a new 4'x6' grid system with more than ample fixture hanging options. Concurrently, Reese's electricians replaced all of the old two-pronged twistlock plugs on the station's tungsten lighting fixtures with grounded twistlock connectors. They also installed new fluorescent worklights above the space.

Next, the Rosco/ET dimmer bars were installed on the grid, then the power supply cable coils were run out to the dimmers from the catwalks and secured along the grid pipes. DMX cables were run from the dimmer bars back to the DMX outlets. In some cases the DMX output boxes were mounted on the catwalks, in others they were brought out to locations on the grid, depending on the placement of the IPS dimmers.

Occasionally, promotional and HDTV spots are shot in the production end of the main studio with film-style electrical distro systems brought in by outside production companies. One advantage of the new power and control wiring configuration is that, if needed, both power and control outlets can be dropped from the catwalk level down to floor level to supply the distro boxes and to provide interface with the permanent lighting system.

Finally, under the direction of WMLA's Bill Merrill and Altwegg, the lighting fixtures were rehung and focused. In 1992, KXAS had purchased Videssence fluorescent lighting to light the newsdesks, in part because it could bypass the old two-wire electrical system with grounded house power available from a previous renovation of the station's office spaces. Due to a limited budget at the time, the Videssence lighting package had been designed and hung by Merrill with lightweight chains. As a part of this current renovation, Matthews telescoping hangers were purchased to replace the unwieldy chains. Final focus of the lights was completed on Friday and the station was again broadcasting from the newly renovated studios on Saturday.

Prior to the work on KXAS's main studios in Fort Worth, WMLA installed a small lighting grid and IPS dimmer system in the new Dallas news bureau, keeping both facilities on similar systems and allowing the flexibility of moving IPS dimmer bars between the two locations should the need arise. KXAS now has tremendous flexibility to expand or reconfigure its studio lighting system based on future needs.