On the road with the Motor Racing Network


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As the summer begins, stations take to the road in full force. For most stations, the remote broadcast is a supplemental element to their programming schedule. In the case of the Motor Racing Network (MRN), location broadcasts are the routine and not the exception.

To refer to MRN's latest project as simply a remote vehicle is an understatement. When Jim Moody, director of engineering of MRN, began designing a new location vehicle, he spent several months gathering information and determining the needs of the new facility. It had been several years since MRN built its last vehicle, and technology advances provided new possibilities in audio routing, recording and portability.

A large part of MRN's programming is race events. MRN covers more than 100 racing events a year. The race schedule spans about 10 months in locations all over the country, so the broadcast schedule leaves little room for equipment downtime. In addition, the network also provides a weekly talk show and several daily program elements to more than 700 affiliate stations. While some of this programming originates from the offices in Daytona Beach, FL, the broadcast fleet provides a large amount of material. To accommodate this demand, the network needed a new vehicle that could be set up on location in a minimal amount of time. As the project manager and designer, Moody had a full agenda before him.

Designing the new trailer required a completely different approach than designing a fixed broadcast facility. The Featherlite trailer, chosen because of its reduced weight and the company's experience in providing customized interiors, presents a finite space. Once built, the vehicle cannot exceed 80,000lbs. gross weight. Also, there are specific weight load points that must support any internal equipment and construction. In addition, the trailer uses an air-ride system to prevent unnecessary jarring of the equipment inside. Despite these limiatations, the vehicle houses three studios, a voice booth, an office, four work desks, a kitchen, abundant storage and enough electrical power to run on its own for a week without shore power.

When a studio facility is designed, there is some flexibility to adjust the construction elements as needed. In most cases, the area above the ceiling is considered an open space. Ducts and conduits can be routed as needed with little effect on another system. With the trailer, there is no extra space. Every decision affects another element. If an additional inch of clearance is needed for a pocket door, that space must be taken from a cooling duct, cabinet or some other area.




The monitor above the edit suite rack provides system information and provides race-event information.


The world feed panel provides convenient connections and metering for audio sources and destinations.


The control room rack features its own HVAC and filtration system.


Outside the edit suites, showing the rack and entrance to the galley.


The talk studio.


The control room.


The prep area.


The edit suites.

To add to the design complexity, this is a mobile environment. Everything must be provided with a tie-down or fixed storage point. The trailer also has two side extensions, called slide-outs, to create additional space when in use. These slide-outs must retract cleanly for transport.

During a race, there can be as many as 10 talent mics covering the event. There are two announcers in the announce booth in the stands, as many as four announcers on each turn, up to three announcers in the pits and perhaps an additional announcer for the field. There are also prerecorded elements and native sound from the event. Every race is a major event, and these steps are repeated every weekend for 10 months.

The final program audio mix is sent to the satellite uplink truck — a separate vehicle — which is parked near the trailer. The trailer is equipped with a Telos Zephyr Xstream and Comrex Matrix, which can be used during the race for contributed elements, but also serve as backup audio paths in case of an uplink problem.

Fixed but flexible

While the design of the vehicle was based on the current needs of MRN, the overall design and many of the equipment choices provide flexibility to meet demands that may arise in the future. The digital consoles by their nature provide flexibility in routing and control, but additional insurance was needed. Because the lines between audio and data are becoming less clear, the vehicle was wired with shielded CAT-5 cable. With this infrastructure in place, the Radio Systems Studiohub+ system was used for the interconnections. The modular connectivity of Studiohub enables MRN to make changes quickly without pulling additional cable or worrying about connector choices.

Most of the live audio sources originate from outside the vehicle, so the Studiohub world feed panel is used extensively. This panel provides an interconnection point and provides transformer-isolated XLR and binding-post terminals. In addition, the panel provides metering of all the sources appearing on it, providing an additional point of confirmation. Different events use different methods of transporting audio around the track, so the different connectors provide the flexibility needed for on-site adjustments. An additional advantage to having the binding posts is that they provide a convenient test jack when troubleshooting.

During an event, the trailer and the announce booth are in constant communication. While it would be possible to connect these locations with wire or fiber optic cable, this is not practical. Every venue is different, and a stable physical connection is not always possible. Instead, MRN uses a Bitrage CR45-A, license-free, spread-spectrum wireless system to provide a 45MB/s link between the two points. This link is then tied to a Terawave INT multiplexer on each end, which provides a 10/100BaseT Ethernet path, three video channels, six audio channels and some ancillary connections. This provides the announce booth with complete connection to the trailer. The event producer runs a laptop that accesses the Audiovault system so he can trigger audio events directly.

The equipment taken to the announce booth is housed in two 5RU road cases. These contain the Terawave multiplexer, Bitrage radio, Studiohub mixer and a UPS.

Announcers around the track use Lectrosonics wireless systems to stay in communication with the trailer. In some cases, dry copper pairs are used if the RF link cannot be established because of local terrain or structural interference issues.

Talk studio

The tour of the interior begins in the talk studio, which seats two guests and isolates them from the control room. The large glass window provides a clear view between the producer and the talent. Two Audio-Technica AT4040 mics and an Audion Labs Voxpro audio editor, which can be used for offline recording, are used in this studio. This studio sees most of its action before a race and when the truck is used for a live MRN show. This studio also sees many drivers and racing celebrities, who use the recording facility for interviews or recording commercial endorsements.

In case of a rain delay, the booth announcers will come to the truck and report from this studio, taking advantage of the resources the vehicle has to offer.

The glass is etched with the racing checkerboard motif, and a fiber-optic light rope, imbedded in the glass frame, provides added contrast. The light rope accent and checkerboard pattern are carried throughout the vehicle's interior design.

The countertop panels near the window provide access for the mic cables, and they also conceal additional audio connections, including headphone jacks and data connections. Each room has its own HVAC controls, which eliminates hot and cold spots in the vehicle by providing climate control for a small area.

Behind the talk studio, toward the front of the trailer, is an office with a desk and a couch. This serves as a green room before interviews and the producer's work area before and after a race.

Control room

During a broadcast, this room serves as the central control point. All the audio sources are routed through this room.

During a race, MRN provides a program mix to its broadcast affiliates. It also provides an audio feed to the raceway PA system. Additional feeds may be provided on site as needed. With so many dynamic audio sources available during a race, MRN needed a way to route sources and change assignments quickly. In addition, to simplify the equipment needs of the announcers around the track, a separate IFB system is not used; rather, the console is reconfigured for on air, local breaks and network breaks.

The Mackie d8b console was chosen for this application because of its ability to recall scenes instantly. When the broadcast goes to a commercial break, sources are reassigned to different output buses, creating an offline communications network and eliminating the need for a separate IFB system. Further integrating this process, the Audiovault system is tied to the console via MIDI. When the Audiovault system is told to start a break, it issues a command to the Mackie console, recalling a different configuration that provides the offline communications system, provides commercial audio to the network feed and provides house audio to the PA. The announcers are free to communicate during the break.

When there are 10 seconds remaining in a break, the Audiovault system plays an announcement through the IFB, which is the signal for everyone to be quiet and stand by. The on-air scene is then recalled and the show continues. This is all done with the press of a button.

Prep area

When the vehicle is parked at a venue, the trailer is disconnected from the cab and auto-levelers adjust its position. Two slide-outs are then extended to provide more internal space. These extensions are moved in and out with a button. The preparation work area is in the driver-side slide-out. These four desks provide a work area for the race announcers. Each position has its own drawers and cabinets to store materials and supplies that each individual may need.

A fax machine is mounted at the end of the counter, and each desk position has a telephone and Ethernet connection.

The countertop is made of Corian, while the cabinets and drawers are made of laminated wood. As was done in all the rooms, the underside edge of the counter is traced with a fiber-optic rope light, which adds a decorative touch to the vehicle. Featherlite manufactured all the furniture and installed the rack rails to mount the equipment.

From the angle shown here, the control room is through the door and up the four steps. To the rear of the trailer is a galley with a refrigerator, a stove and a bathroom. Directly behind the prep area in the other extension are the two edit suites.

Before the broadcast begins, this area hosts the pre-show meeting, where everyone involved in the broadcast goes through the broadcast schedule. The group is given final instructions and information before heading to their specific race location.

Edit suites

There are two edit suites in the passenger-side extension. These suites are mirror images of each other. Edit suite B is shown here. The room layouts complement each other, not so much for design reasons, but to accommodate left- and right-handed users. The suites are small rooms, capable of seating one person.

Each suite is equipped with a Yamaha 01V console, Audio-Technica AT4040 mic, Broadcast Electronics Audiovault workstation, Radio Systems CT-2002 timer, Denon DN-M2300R dual minidisk recorder, Tascam C-222 cassette/CD combo, Studiohub switcher, Alesis M1 active MK2 monitor and a Furman PLP power conditioner. There is an audio input and output panel for producers to connect a laptop running an audio editor or any other audio device.

There are two sources of light in each suite. A 12V incandescent lamp provides a great deal of light on its own, but in this small space, this single lamp creates a large amount of heat. If four lamps were installed, the air conditioning would run non-stop to keep the room cool. Instead, there are four fiber-optic spots near each corner. These spot lights provide a brilliant white light, no heat and can be focused to illuminate specific work areas. The fiber-optic light source is in the upper section of the trailer.

There is a rack between the two suites that houses the Audiovault servers, a DBX 2231 program equalizer and a DBX 1066 compressor and limiter for each suite. This rack can be accessed through an opening under the edit suite cabinet. Amazingly, there is sufficient space for a technician to stand up and comfortably work.

Finishing touches

The main racks in the control room are sealed and cooled on their own filtered-air system, and provided with a positive-pressure air flow to ensure that the equipment stays clean. This may seem like overkill, but air quality can never be guaranteed in a mobile environment, particularly one that travels to events centered around combustion engine exhaust in locations that are typically rural and dusty.

There are several storage and access panels around the outside of the vehicle. One access panel toward the front houses the world connect panel. Another provides the shore-power connection. The rear liftgate provides easy access to the upper storage area, which provides a large storage space. A Will-Burt 42' mast provides a clear line-of-site platform for the antennas.

The trailer is highly functional, but the attention to design details make the overall presentation stand out. The MRN broadcast trailer exceeds its practical function to create a remarkable showcase on wheels.


The pit crew

Jim Moody managed the entire project and handled the equipment integration and installation. The project was authorized by David Hyatt, MRN president. Audio wiring plan and installation was done by Radio Systems. George Waters & Associates provided the IT services. Featherlite provided the trailer and built the interior. Broadcast Electronics installed the Audiovault system. SCMS provided the majority of the remaining studio equipment.


Equipment list


Advantest R3465 spectrum analyzer
Alesis M1 active MK2 monitor
Alesis RA300 power amp
Aphex 320A Compellor
Audiocom SPS-2001
Audion Labs VoxPro
Audio-Technica AT4040 mics
Bitrage CR45-A
Bose outdoor speakers
Broadcast Electronics Audiovault
Comrex Matrix
DBX 2231 EQ/comp/limiter
DBX1066 comp/limiter
Denon DN-M2300R MD recorder
Denon TU-1500 tuner
Featherlite trailer
Furman PLP power conditioners
JVC RX-7020V tuner
Lectrosonics UDR 200C receivers
Lectrosonics UM 250C transmitters
Lectrosonics UMC 16A
Mackie d8b
Mackie HR824
Mackie HRS120
Microboards CWR-424 duplicator
Middle Atlantic shelves and drawers
O.C. White mic booms
Panasonic plasma display
Panasonic SV-3700 DAT
Popfilter pop filter
Radio Systems CT-2002 Master Clock
Radio Systems CT-6 GPS master clock
Radio Systems DA-4×4a distribution amps
Radio Systems StudioHub+
Radio Systems StudioHub+ 4×1 switchers
Radio Systems StudioHub+ World Panel
Rane HC-4 headphone amp
Sony MDS-E10 minidisk
Tascam CC-222 cassette/CD
Tascam CD-RW402 dual CD recorder
Telex SPS-2001
Telos Zephyr Xstream
Terawave INT multiplexer
Will-Burt 7-42
Yamaha O1V mixer



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