Digital ends the analog era

By Alex Emslie
STAFF WRITER

Congress has mandated that all television stations cease broadcast of analog signals by June 12, 2009. An estimated 15 million American households who depend on free, over-the-air broadcasts as their only source for local news and emergency information will be affected by the national switch to digital.

Households dependent on OTA broadcasts — those who don’t subscribe to either cable or satellite services — have several choices to prepare for the digital transition.

Most newer televisions have digital tuners built in and will be unaffected by the switch. TV sets with labels that read “Integrated Digital Tuner,” “Digital Tuner Built-In,” “Digital Receiver,” “Digital Tuner,” “DTV,” “ATSC” or “HDTV” can already process digital signals, according to the government Web site dtv.gov. The National Telecommunications and Information Administration encourages consumers to check their owner’s manual or contact their television’s manufacturer if they are unsure.

People who want to keep using older analog TVs can apply for up to two $40 coupons – available through the NTIA’s nationwide coupon program — toward the purchase of a digital to analog converter box. The boxes range from $40 to $80 and are available at most retail electronics stores.

The original Feb. 27 deadline was postponed. “Too many Americans were at risk of losing OTA television service,” said Anna M. Gomez, NTIA’s acting assistant communications and information secretary, in her recent testimony before Congress. Nielsen, which rates TV shows,  estimated in January 6.5 million households were unprepared for the digital transition.

The coupon program ran out of funding Jan. 4, and the waiting list reached of 4.2 million by March 17. The DTV Delay Act changed that deadline to June 12 and the American Recovery and Reinvestment Act provided an additional $650 million for the NTIA.

What is the difference between digital and analog TV?

TV signals have been broadcast in analog since primitive prototypes of the first electronic sets appeared in the early 1900s. An analog signal is a continuous electronic wave that can be transmitted either through a wire or over-the-air. The wave length and amplitude of the signal are an electronic copy of whatever information is being transmitted; for example, light or sound.

Digital signals work with only two levels of amplitude, called nodes. Digital is either on or off, high or low, true or false, one or zero and so on.

Digital signals can be compressed more than analog signals. More information can fit into a signal, or channel, which translates to a clearer picture and higher quality sound. Also, while both signals get weaker over long distances, digital remains either on or off. If the signal is strong enough for an antenna to pick up, it will transmit a clear picture regardless of distance.

More OTA channels might become available after the switch to digital is complete. Digital broadcasting allows for multicasting, or the broadcasting of more than one channel within a single signal.

Digital offers more of the radio spectrum, for less

Improvements to picture and sound quality, reception, and the number of channels that are provided by all digital broadcasting will free up some of the limited radio spectrum. The Federal Communications Commission, which regulates usage of the radio spectrum through licensing, plans to use the newly freed frequencies for emergency services communication and wireless development.

The DTV transition affects frequencies running from 698-806 megahertz. Those frequencies are currently used by television broadcasters, but they will be made available to emergency communications after June 12.

According to an agency news release, the FCC plans to use portions of the radio spectrum made available by the digital transition to create a “nationwide, interoperable public safety broadband network [that] would enable police, fire and medical personnel to communicate with each other in emergencies.”

The First Responders Coalition applauded the FCC’s initiative to use 700 megahertz frequencies to promote interoperability between agencies. “As was tragically evident on September 11, 2001, and again in the wake of Hurricane Katrina, the communications systems of public safety departments are not interoperable,” wrote Executive Director Steven Jones in a letter to the FCC. “The most immediate step in solving the interoperability crisis is to reallocate spectrum in the 700 megahertz band from television broadcasters to First Responders as part of the digital television transition.”