This article attempts to outline some of the choices involved in building a truck today, both from a technical and a production perspective. The designer must consider all of the various methods of production and their implementation.
The choice between analog and digital monitors is based mainly on cost and/or engineering factors. Different options must be weighed within the scope of the project — there is no one set solution. For instance, this monitor wall uses analog for the small monitors and digital for the large displays.
Each topic below could easily be the subject of its own magazine article. This limitation notwithstanding, the article attempts to point out, in general terms, the major items that must be evaluated before starting on a vehicle design.
The quandary
Building a remote broadcast truck today is an enormously challenging task. Recent advances in equipment design have made the actual system engineering more straightforward in some ways. But the question of just exactly what to build has become increasingly difficult. The choices and realities of format and aspect ratio, and today's economic considerations, have added several layers of complexity to the decision-making process.
It was not long ago that the main considerations in putting together a large-scale television truck were more or less limited to relatively simple decisions regarding specific equipment manufacturers. One simply needed to decide this camera vs. that camera, what brand switcher to use, what audio console, etc. Ok, maybe it wasn't so simple. It was, however, a lot more simple than the multitude of choices facing the truck builder today.
In the past, broadcasters could be fairly secure in assuming that their multimillion-dollar investment would enjoy a lifespan that would have a chance of retiring their investment debt. Now, not only is there extreme economic pressure, but technology that once would have remained viable for five years or seven years, or even longer, is no longer secure from rapid obsolescence.
Adding to the confusion are the aforementioned issues of format and aspect ratio, which include HD and SDI digital with all their various flavors, and analog NTSC for the immediate future and possibly even longer. New trucks must be multi-standard vehicles, requiring additional equipment to allow either simultaneous production in multiple formats, or the ability to switch between formats as clients' needs change.
Audio, while equally important as video to the production, at least presents fewer core technical choices at the moment. The main audio decisions will probably focus on analog vs. digital (in the remote truck world), and perhaps side issues such as surround sound and fader automation. The question of digital audio — where and how much to use it — is bound to arise. Even so, it is straightforward and relatively easy to answer.
There are other decisions that must be made during the initial design phase, including type of monitoring, tally display and intercom, as well as the physical details of layout, HVAC, and power and weight distribution.
Perhaps the first, and arguably the most complex, step truck builders must take is to decide what video formats the truck must produce, and how to monitor them.
Truck eyes
Let's begin with the cameras, the “eyes” of the truck. Camera manufacturers have done an incredible job of creating cameras that can be easily switched among various formats and aspect ratios. Some of them can even output multiple formats simultaneously. Keep in mind what the truck needs to produce. Is the end product to be NTSC analog, SDI digital or HD? Most likely, on any given day, it could be any of these.
The actual system engineering for a remote truck might be easier — thanks to advances in equipment design – but the complexity of format and aspect ratio makes deciding what to build in the first place a tougher question than ever.
An equally important issue is the type of camera cable the truck will employ. Thankfully, today's choices are limited to just fiber and triax. Fiber, while providing some potential advantages, is a lot more expensive to maintain and much more fragile than triax. It also suffers from the expensive disadvantage of not being pre-cabled into the majority of stadiums around the country. But, over time, the majority of venues around the country will likely install permanent fiber, as they did with triax many years ago.
The cameras chosen will need to be able to go either way, or at least be convertible at minimal cost and difficulty. Different camera manufacturers accomplish this in different ways, so be sure that you and your consultant evaluate each one against the specific needs of the project. It is also likely that the camera manufacturers will implement multiple-cable design at an attractive cost point, which will allow either type of cable to be used with little or no camera conversion.
Another decision is whether to have the camera output multiple formats right out of the CCU, and if simultaneous multiple formats are needed at all. A variety of “in the CCU” output solutions offer a bewildering array of options. And, of course, external conversion is also an option. The truck may end up with a mix of both. This decision will depend largely on the type of monitoring being used (discussed separately below).
If the truck must produce multiple formats simultaneously, the complexity can increase exponentially. One trend that may alleviate some of this complexity is that some end users may have started relaxing their requirements regarding output conversion. For example, it's theoretically possible to produce a show in HD/1080i or in HD/720p and convert the output to whatever the secondary standard may be — either the alternate HD format, SDI or even NTSC. In the case of NTSC, there are additional considerations such as graphics insertion and aspect ratio, which may require a compromise in camera framing in the HD show. While these are certainly critical production decisions, their technical implementation can be even more critical and sometimes bewildering, as well as costly. Fortunately, some, if not all, multi-standard cameras offer various monitoring options at the camera viewfinder, allowing camera operators to see the framing for both 4:3 and 16:9 simultaneously in most cases.
Operator eyes
Depending on the formats the truck supports, truck owners may decide a mix of analog, digital and HD monitoring is required. The large plasma displays here were fed HD signals.
The production monitor wall is another excellent example of conflicting decisions facing a prospective truck owner today. Standard design would implement a tube-type monitor wall with 75 to 100 small black-and-white or color monitors and at least two 20-inch color monitors for program and preview. Today, there are additional choices and technical/production considerations that must be evaluated. Because this truck is, at some point in its life, going to be called upon to produce 16:9 shows, should the monitoring therefore be primarily 16:9? Should it be capable of 16:9 switching? If the truck owner is shooting a show in 16:9, and has clients that want a 4:3 show as well, a decision will need to be made as to the monitoring format. Perhaps a mix will be required. A 16:9 image on a 9-inch monitor can appear rather small. Broadcasters may wish to implement multiple monitor sizes in the main display wall.
Another possibility would be implementing one of the various “virtual” monitor walls available today. A side issue to monitoring is tally display. On-screen tally is necessary with any of the virtual monitor wall concepts. Otherwise, you must choose between the built-in tally light on the monitors, or an under-monitor display (UMD) system. A virtual monitor wall may have the added feature of providing essentially any display right on the wall itself, including operator names, or audio and video level meters.
Yet another decision in video monitoring is analog or digital. For all intents and purposes, this is a cost/engineering decision, because the difference in the picture quality (as viewed in the production room on the smaller monitors) is not sufficient to sway the decision. It is possible that, in the virtual monitor wall scheme, digital may have significant engineering advantages. It is also possible that, if the rest of the truck is digital, the addition of analog monitoring could add a layer of complexity and cost that could be offset by the use of digital monitoring. There is no one simple answer to this question. It must be evaluated within the entire design and production specification of the proposed vehicle.
Tape vs. disk
The tape room is another area of the truck that requires special attention. Today's usage still demands some standard tape formats, such as digital and analog Beta, and various flavors of disk-based recording. Sports production requires, at the very least, an EVS-type system, and sometimes more than one. This could be in addition to a Profile or other mass-storage device. The time is rapidly approaching when the entire “tape” room may migrate to a server-based system, regardless of the production format. This dictates that the core design of the truck be flexible enough to grow with the changing formats, or be upgradable with a minimum of fuss and expense. It is possible to implement a design that will allow for major future changes with a minimum of downtime and expense.
Careful cable choice and neat installation can help alleviate airflow and weight issues in truck construction.
Nuts, bolts and wires
The actual physical construction of an HD/multiformat vehicle needs special attention also. The issues of production space, heat, overall weight, weight distribution, airflow and power are critical in a truck of this size and complexity.
Cabling in the high-data-rate world of high-definition video may need to be larger, and consequently heavier, than standard digital or analog cable. This larger cable takes up more space, and can lead to decreased airflow and potential heat problems if not implemented properly. The same holds true with digital audio cable — particularly if twisted pair is selected over coaxial. Careful system design specifications and integration practices can minimize the need for larger cable.
This can alleviate the inescapable airflow and weight issues, as smaller is better when installing wiring. Experienced systems integrators can put the correct cable where it is needed while minimizing the space it occupies. Overall weight must always be considered when engineering a large-scale truck. With proper engineering, up to 1000 pounds can be saved by careful cable selection alone. The cost of cable, and even system integration, diminishes rapidly when factored into the overall cost of the truck.
By selecting the proper system designer, you will enjoy savings in equipment (selecting the proper piece for the job) and gain long-term advantages such as simplifying daily operation, maintenance, and future changes and upgrades.
Generally speaking, digital production equipment may be expected to produce more heat, in roughly the same space, than the analog equivalent. So, airflow and overall cooling capacity, as well as AC power considerations, will need to be carefully designed and specified. Choosing a virtual monitor wall instead of a CRT monitor will further save weight, space and power.
As a prospective truck owner today, you face a bewildering array of choices in production equipment. And you must make these choices before the first walls and wires are put into the CAD drawings. The issues are complex and interrelated as never before in our industry. But careful design specifications in the planning stages will lead to a truck that can handle the various formats necessary in production today, and well into the ever-changing future.
Barry Bennett is the owner of Bennett Systems, a firm providing systems consultation, engineering and integration.
