Another DTV threat
Cutting power could kill the service before it gets started
Nat Ostroff, Sinclair Broadcast Group -- Broadcasting & Cable, 5/5/2002 8:00:00 PM
Sinclair has always viewed the success of the DTV transition as dependent on the ability of our signals to reach an over-the-air audience. Long before we discovered that the 8-VSB system was flawed, Sinclair fought the FCC, MSTV and the NAB for the need for increased UHF transmission power to be able to reach indoor antennas. We won that battle, and the Maximization Principle was written into the rules.
When the FCC changed the ground rules and allowed TV stations to transmit at low power for DTV, many broadcasters welcomed it, but that decision may have fed the DTV transition a poison pill. While low-power operation saves on the station's initial investment and the operating-power bill, it does great harm to the public's perception of the new digital service.
It is fully understandable, from a political point of view, that the FCC would allow the low-power option in order to be able to report that a large percentage of stations have met the DTV deadline, as amended. However, what is very disappointing is the lack of recognition of the long-term impact of that action. Initial operation at uselessly low power is to condemn over-the-air DTV to a long and painful period from which it may never recover.
There are a host of reasons for not launching over-the-air DTV at low power. For one, the FCC Table of Channel Allotments was based on the assumption that all stations would operate at their assigned power levels. This ensured that the interference between stations would be manageable. When DTV stations operate at much lower power than originally assumed, they are subject to interference that would otherwise have been overcome.
Another reason is the adjacent channel assignments for DTV. It is one thing for the DTV receiver to separate adjacent channels when they are close in power level. It is quite difficult to separate adjacent channel signals if they are separated in power by a ratio of 100 to 1 or more.
Perhaps the most egregious major new development is the current, widely recognized understanding that the FCC's DTV planning factors are in error by a factor of 10 or more. In other words, DTV reception, as calculated by the FCC and used to determine transmitted power levels and coverage, has been too optimistic by 10 dB. This means that the predicted coverage of a DTV station's signal is currently overstated, using the FCC planning factors, by more than 60%. At lower powers, the coverage is practically useless.
Low-power operation of DTV will eliminate the most important over-the-air audience for the new service: the home viewer with an indoor antenna. In short, low power really means no power to most of our audience and certainly eliminates indoor reception in most cases.
Whatever happened to the broadcasting industry's principle of always striving for the best over-the-air coverage and reach? Have we become so complacent that we abandon the over-the-air audience and slip into a slavish reliance on cable delivery? The birthright of our industry was and still remains the ability to reach our audience on a wireless basis. That and that alone distinguishes the broadcaster from being just another cable programmer. It is also worth noting that an FCC license and the accompanying RF spectrum are not a requirement to be a cable programmer.
The FCC has made a short-term political decision that will allow it to dodge the bullet that its continued technical mismanagement of the DTV rollout has created. It will be able to say to Congress that it got most of the DTV stations in the U.S. on the air on or close to its deadline. On the air, yes, but not into America's living rooms. As broadcasters, we should remember that operation at low power is an option, not a requirement. We can and should do better for our audiences and ourselves.
Our industry's grateful acceptance of this economic escape hatch stands as testimony to the failure of the DTV/HDTV vision put forward more than a decade ago. It also is evidence of how far our industry leaders have strayed from the original ethic of our industry. That ethic was once to provide maximum free, over-the-air service. The unintended consequences of the FCC ruling may very well be to kill over-the-air DTV service or, at best, marginalize it out of existence.
Putting the poor performance of the 8-VSB standard aside, the consequence of low-power DTV rollout is that the public will not be able to receive our DTV signals. Over-the-air DTV service will be relegated to a historical backwater, and the well of public opinion will be poisoned for many years to come.
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