The transformation of WTVI-TV

WTVI in Charlotte, NC, has served the greater Charlotte/Meklenburg County since August 1965. It first operated strictly as a department of the Charlotte/Mecklenburg school system, becoming an independent community PBS station in 1983. The FCC mandate requiring all U.S. TV stations to convert from analog to digital transmission led non-commercial stations, such as WTVI, to prepare for their conversion deadline of May 2003.


The audio control room consists of Dolby-E broadcast implementation, which allows for surround sound throughout the production and broadcast process. Photos courtesy TGS.

While part of the goal was to meet that mandate, station management had a broader vision. They wanted to transform a 1990 vintage single-channel analog broadcast facility into a state-of-the-art multichannel digital facility that would go far beyond merely satisfying the FCC mandate.

There was a keen desire to have a fully functional HDTV and DTV facility rather than just a plain vanilla pass-through network that simply upconverted current analog programming to DTV. The station wanted to be able to originate digitally, live-to-air and edited-to-tape in both DTV and HDTV, with 5.1 surround sound.

The station has always had post-production facilities in Charlotte, serving a variety of outside clients within their funding guidelines. This helps offset the amount of public funds required to maintain an operation without interfering with their main mission of public television. Therefore, any transition plan for the broadcast plant had to also encompass editing facilities that provided full DTV/HDTV editing, complete with 5.1 surround sound production, and allow WTVI to maintain the same level of operations as in the analog world.

Streamlining operations was a key issue in planning for the facility, so as to minimize the need for operational funding from public sources. Automation played a key role in decisions made as the project moved forward, in order to allow the station to easily program multiple channels without staff increases.

Last of all, there was a need for clear documentation – a drawing and wiring database that would assist in making future upgrades and troubleshooting. This was sorely needed, as the analog plant had absolutely no wiring documentation at all.


HDTV editing is built around the Discreet Logic smoke platform, providing full HD capability, while SD editing is done in two rooms using the Discreet Edit system.

The challenge went well beyond a simple conversion. PBS facilities have a large library of analog material for iTV and other programming, so a large percentage of the existing analog plant had to be immediately converted to digital to interface with the new digital plant. In addition, there had to be the ability to deal with new formats as they might emerge.

In fact, upgradability was a major factor in the design process. This was not just a matter of buying the latest technology. It meant that each technology had to be evaluated for how it could grow, expand and absorb new technologies. Even the wiring layout and flow was carefully considered, making sure it was logical, clear and easily changed as the facility’s needs changed. In many cases, the plant was pre-wired for future options to make those transitions easier.

There were acoustical challenges as well. This went beyond just adding acoustical treatments to walls. In fact, the edit suites, live audio production room and audio post areas had to be rethought and redesigned to create spaces conducive to 5.1 audio production. HVAC and airflow had to be examined and tuned to minimize noise in several spaces. There were even changes in the studio, as 50 percent of the hard cyc was removed to improve the audio characteristics in the new studio.


Studio control is designed to be functional with a logical workflow, putting the equipment the staff needs at their fingertips.

Despite these kinds of changes, the desire was to keep the building modifications to a minimum. The entire project was funded by a government grant of ten million dollars, and WTVI wanted to preserve the lion’s share of the grant for equipment and systems. To prepare for this project, the station extensively interviewed four systems integrators. Choosing an integrator was not simply a matter of determining whether the integrator was capable of this kind of cutting-edge project. They also had to be willing to work with WTVI, not as an expensive turnkey project, but rather as a partnership between the integrator and station staff. In the end, WTVI selected TGS of Chantilly, VA.

Multiple sources of public funding meant that the equipment list had to go out to bid, and so, in conjunction with TGS, WTVI deployed a large public bid with over 1000 line items. After evaluation, equipment was chosen and TGS began their work with the help of the station staff.

Master control is the nerve center of the broadcast plant. Built around the Philips (now Thomson) Saturn master control system and routing, it is designed to be run as a one-man operation, with easy access and control of automation, switchers and routing. Louth automation plays a key role here, allowing one person to effectively stand watch over the multiple channels. During the day, these include four SD channels and, in the evenings, they include one HD channel and two SD channels. Master control is in a separate enclosed room away from the noise and activity of the machine core or major walkways, but the glass walls around this room allow touring groups to watch the operation of the station without disturbing the operator.


The studio equipment consists of four Philips LDK 6000 1080i cameras, ARRI lighting and QTV prompting, which is fully computerized and controlled from the control room or studio.

Studio control is designed to be functional with a logical workflow, and it provides the staff with the equipment they need at their fingertips. Monitor walls are actually Miranda Kaleido feeding four 42-inch plasma displays. This allows easy change of monitor setups for producers and programs, and keeps the monitor count down. The fully functional HD production room includes the Philips Seraph HD production switcher with two-M/E busses, which was chosen for its power and flexibility. There are also graphics and titles created in full HD by the Pixel Power Clarity HD graphics system, and effects built on the Accom Dveous HD and its industry standard user interface. Programs are produced in full 1080i HDTV, and can be sent to air as HD or recorded in virtually any format for use later by the station or clients.

In the studio are four Philips LDK 6000 1080i camera, ARRI lighting and QTV prompting, which is fully computerized and controlled from the control room or the studio.

Audio is also a major consideration. Because of the desire to be able to produce 5.1 audio at any stage of production or post-production, WTVI chose to put in place the first broadcast implementation of Dolby-E throughout. From the Studer 950 audio mixer, to the editing capabilities of the full Digidesign Pro-T 24 system, to the wide array of Dolby processing options, surround sound audio is available throughout the production and broadcast process. There are three editing suites at the station. HDTV editing is built around the Discreet Logic Smoke platform, providing full HD capability, while SD editing is done in two rooms using the Discreet Edit system.

As programs and interstitials are completed, they can be stored and played back on a Philips (Thomson) Media Pool six-channel server, controlled via Louth automation. When programming is no longer needed immediately, it is archived to a StorageTek tape backup system, also controlled by automation and Avalon software.

The facility uses Harmonic HD and SD encoders for processing, and Thales stream management to groom the signal and add PSIP information. The signal is then sent to the Thales solid-state, liquid-cooled transmitter via Microwave Radio TwinStream radios for transmission on DTV Channel 11.


The master control is built around a Philips (now Thomson) Saturn master control system and routing, and is designed to be run as a one-man operation.

Great care was taken with the infrastructure. Different color wiring for each signal type is reflected in the final drawings, making follow-up and troubleshooting easier. The conversion and terminal gear is largely Miranda, ranging from DAs to conversion equipment to the Aquila upconverters. ADC patching boxed the router. Leader and Tektronix test equipment ensures quality control throughout the plant at key QC points.

Detailed pre-planning and engineering minimized problems, and made sure that all of them had fixes before the project was complete. In addition, extensive manufacturer training got staff on track once the systems were in place.

The facility went on air in April 2002, and has far exceeded the simple mandate of the FCC. But more importantly, it has met the larger goals of providing Charlotte with a facility that meets the multichannel challenge, providing up-to-date HDTV production and post-production facilities, and streamlining workflow and improving efficiency.

Wray Ware is the chief engineer at WTVI-TV.

Design teamWTVI-TV: Wray Ware, chief engineer; Tom Green, senior maintenance engineer; Brent Kennedy, chief audio engineer; Thomas Brunet, maintenance engineer; TGS: Joe Hickey, senior design engineer; Willy Halla, executive vice president for engineering Equipment list
Thales Optimum liquid-cooled 2.5kW solid-state transmitter; Microwave Radio TwinStream 13GHz STL system; Discreet fire HD edit system; Discreet smoke SD edit system; Discreet SD edit system (Edit); Studer D950B live audio console; Philips LDK 6000 HD studio cameras; Pixel Power Clarity HD graphics system; Accom Dveous HD DVE; Philips Seraph HD production switcher; Harris automation system; Myers Pro-Track traffic system; Sony HDW-700 HD field camera/recorder; Philips SD and HD Media Pool video servers; StorageTek cart archive system; Philips Venus router; Philips Saturn master control switcher; Philips Dune AES audio router; Panasonic D-5, DVCPRO VTRs; Sony HDCAM, Digital Betacam VTRs

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