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Digits Over the Air

The transition to digital over-the-air TV is nearly complete. So what does that mean for videographers?

While most of our discussions of television are generally about either criticizing the medium as a whole or trying to get distribution for our own productions, the technical aspects of television distribution generally never enter into the equation. However, we are at an interesting technical crossroads as the digital television transition nears its conclusion (and as some stations have been on the air in digital longer than 10 years at this point). As such, the fork in the road for this discussion goes in two different directions: what it means for the TV viewer and what this means for videographers.

To the TV Viewer

While we've been noticing that the average digital TV channel has at least one subchannel (e.g., an auxiliary service provided in addition to the main channel), the irony is that, after the transition is complete, there will actually be less spectrum available for television channels. The 1948 bandplan for TV eliminated channel 1 and reserved channel 37 for radio astronomy, leaving a total of 81 channels available. The first channels hacked off were 70-83, which went away in the 1980s to make way for cellular phones, leaving 67 channels available. Now, elimination of channels 52-69 for public safety radio leaves a scant 49 channels available. And, to compound the bandwidth impact, a group of consulting engineers calling themselves the Broadcast Maximization Committee proposes reallocating all AM stations to channels 5 and 6.

This is not to say that there will be no analog signals at all after February 17, 2009. Class A, low-power and translator stations may remain analog after that magical date. It's only full-power stations that must be digital after that date. However, some Class A, low-power and translator stations have applied with the Federal Communications Commission (FCC) to "flash-cut," to go from transmitting their current analog signals to transmitting digital signals instead. This means that, for those particular stations, there won't be a transition period like full-power TV stations have had, with two channels transmitting. Instead, on a given day (which may not necessarily be 2/17/09), the station will flip a switch and go from analog to digital transmission.

To the typical viewer, this probably means nothing. (Certainly, the most-impacted group will be those who rely on an off-air antenna to receive their local TV signals, but you already have your converter boxes installed, right? Right?)

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