Centralcasting at WALA-TV


WALA is a spoke station in a centralcasting system; thus, local news is basically the only programming produced live at the station.

WALA-TV, an Emmis Broadcasting television station located in Mobile, AL, recently opened its new facility following a move from its longtime location in downtown Mobile. The move into the new facility marked the station’s transition to digital.

A FOX affiliate serving the Mobile and Pensacola markets, WALA also serves as a spoke station to the Emmis centralcasting hub at WKCF-TV in Orlando. Along with WFTX-TV in Ft. Myers, FL, and WVUE-TV in New Orleans, the station now receives all programming with the exception of local news directly from WKCF.

Digital System Technology (DST) was selected as systems integrator for the new facility, in part because of its successful systems integration work at sister station KHON-TV in Honolulu. It, along with the station engineering staff, began work on conceptual drawings in spring 2000. Following construction, on-site integration began in fall 2001, culminating with the launch of the facility in spring 2002.

The move was necessary for many reasons. Most notably, the previous facility had been expanded three times and the station had run out of physical space. The new site would allow for a full analog-to-digital video upgrade (it remains an analog audio plant) and be ideal for a centralcasting spoke station.

As a spoke station, WALA does not have a master control center. Since all programming besides local news originates from Orlando, there is no need for one. However, the new site featured enough physical space to allow for a master control center in the “hub room” should the situation change.

The hub room currently houses 73 racks for equipment, with space for 100 racks to accommodate a master control center. This space was created in the center of the core. This way, the facility does not require centralcasting. If Emmis Broadcasting ever decides to sell the property, the resell value would not be hampered due to space limitations.


WALA’s production control room features an Ikegami monitor wall with Evertz quad-splits. On the “Front Bench,” from left to right, are the Vinten remote control for the Sony BVP-950 studio cameras, a Thomson Grass Valley Zodiac switcher and a Chyron Duet graphics station.

The equipment racks were built for easy maintenance. For the main set of 60 racks, there are four back-to-back, face-to-face rows of 15 racks. A three-foot-wide corridor between the two sets of racks allows for easy access to the back of the units, as the racks were constructed without back doors. The space allows station engineers to handle maintenance with plenty of breathing room.

The absence of a master control center is not the only attribute that sets the facility apart from most other television stations. The elimination of traditional station programming creates a local news bureau type of environment. While the facility is more complex than a simple news bureau, the absence of regular programming allowed more focus on simplifying local news production. To this end, DST implemented two special systems.


Figure 1. This diagram of WALA’s tapeless news environment shows how the server, editing system and AP news system communicate via the Thomson Grass Valley Multimedia NewsQ Pro interface.

The first is a tapeless news environment created using a Thomson Grass Valley Multimedia NewsQ Pro news playback interface. The install allows news reporters to transfer stories directly onto a Profile server. This system, installed in the main production room along with a Vibrant editing system, uses the news playback system to interface with an AP news system (see Figure 1). As the interface between the server, editing system and AP news system, NewsQ Pro tracks the stories and keeps the playlist current with the newscast rundown. Then, when a producer floats a story in the newscast, the playlist is automatically updated.

This eliminates the possibility of airing the wrong footage, and the need for tapes to be loaded manually. Instead, the operator can take the story directly from the server. Once in the server, the operator can review a story seconds after it comes in electronically from a network, satellite or microwave feed. The user can then play back and begin editing the story instead of waiting for a feed to be completed, as is necessary in a news environment reliant on tapes. The story is also available to multiple users once it’s within the server.


WALA’s audio control room features a Wheatstone TV-80 console.

Story editing is also finished faster. Once the story is on the editing system, the user can transfer a story to the server as a fiber-optic file for play-to-air, making the transfer faster than real time. This provides both the advantages of nonlinear editing and the speed of linear editing. Six identical news edit bays are located directly off the newsroom, along with three Discreet nonlinear editing rooms: one main room and two smaller rooms designed for production of promos and commercial spots. The audio control room features common audio control for communication and one Wheatstone TV-80 console. A Mackie eight-bus 24-8 mixer serves as a floating console and is integrated with the TV-80 for IFB communication.

The second groundbreaking solution is a unique interface designed to automatically segment certain news feeds. Network news feeds come into a station via satellite, and a gap of several minutes will appear between each story. When recorded to a server, the entire feed is saved as one large file. An automated CompuSat system takes care of recording the network feed, but human intervention is required to break the news feed into separate files for each story. With the system already online, the question was how to address this issue.

For a fully automated process, DST developed an interface using an Evertz Quattro quad-split display to sense freeze frames between stories from network news feeds. The display speaks to CompuSat, reads the frozen video as one story ends, stops recording and starts again at the beginning of the next segment. As a result, each story is saved as a separate file with a different name onto the server.

The quad monitor provides an SDI output on the station’s 96x96 Venus router. (In the event that a master control center is ever built, the router has the potential to grow to 160x128.) As a fringe benefit, operators can view up to four channels being recorded onto four different server feeds. Also, because there was an Evertz card tray available on the router, it was a relatively inexpensive solution to a complex problem.


At WALA, Elco audio bulkheads were used in place of a normal patching system to facilitate system reconfiguration while avoiding the problems associated with patchbay corrosion.

At this time, this interface is operable for approximately 50 percent of the news feeds. Many of the feeds are sent in open timecode, which requires human operation to break stories into separate files. The station expects the interface to be used more often in the future as more feeds come into the station as MPEG streams.

Johnny Reece, the station’s director of engineering, had some difficulty with patchbays at the previous facility. With Mobile’s shoreline location, corrosion of the patchbays due to the salty ocean air became a problem over the years. Because of the corrosion, the patchbays became more of a reliability problem than the hardware. To address the growing number of failures due to patchbay corrosion, the integration team systematically removed the patchbays from the broadcast system and implemented point-to-point cabling. However, cabling from one device into another instead of using patchbays requires significant rewiring for system reconfiguration.

To provide the station with the flexibility to alter its system as required by station growth, a unique patchbay-like system was created without using actual patchbays. Instead, three-pin Elco audio bulkheads were used to connect the audio portion of the broadcast system. The audio bulkheads are designed to connect to a device where the cable terminates. A jumper cable connects one bulkhead with another, which is the input that receives the signal. If an input needs to be changed, the cable is removed and plugged into a different input for simple system reconfiguration. These were created strictly for audio – serial digital video connections often conflict with these bulkheads. Some patchbays are used for video, while the majority of these connections are sent directly into the router.

Centralcasting often results in cost savings and operational efficiency. To increase the new facility’s efficiency, Vinten camera robotics were employed to reduce the need for human camera operators. The robotics were designed so human operation is possible when needed, such as during morning newscasts when there is a tendency to go for a more free-form approach. News department employees are called upon when free-form camera work is required. As a result, the facility has the flexibility of traditional camera operation when required, in addition to the cost savings realized by not employing three people to run the cameras at all times.

DST also developed a special switching system to enable operators to bypass the program output and go directly to the M/E preview. This allowed operators to easily switch to a backup path if the regular program output was interrupted.

The new facility features a solid digital broadcast system that meets all of WALA’s current requirements as a spoke station, with the flexibility to grow and change as all successful television stations do. In the event that the facility’s broadcasting needs branch away from centralcasting, the station is well prepared to bring in a master control for traditional broadcast station programming as required. It’s a fail-safe approach for any obstacle the facility may face in the future.

Dwight Crumb is vice president of engineering for Digital System Technology.

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