By Bill Goodwill

Whether you are a consumer or are involved in any aspect of mass communications, your media world changed dramatically on February 18, 2009, the date when all full-power U.S. television stations began transitioning from analog to digital TV.

During this transition period millions of analog TV sets will no longer carry broadcast TV signals unless they are connected to cable, another video service, or to a special digital-to-analog converter available from retailers. Some observers say this transition f represents the most significant advancement of television technology since color TV was introduced in the 1950's. Millions of households nationwide that receive free full power over-the-air television through an antenna will also be affected by the transition. The reason America is switching to DTV is because digital is a more efficient way to broadcast, and it will free up the airwaves for other services, such as public safety.

Early Beginning

The future of the television industry was perhaps defined by an event that occurred on September 6, 1997 in a crowded room at the National Press Club in Washington, DC. It was there that the first live digital HDTV major sports program - a game between the Baltimore Orioles and Cleveland Indians - was broadcast on a 16 by 9 foot screen. The viewers remarked that they could see lines on the player's faces as well as individual blades of grass on the ball field. The commercial birth of HDTV pre-dates this event, when WRAL-HD in Raleigh, NC became the nation's first commercial over-the-air high definition TV station.

On February 28, 2007, the DTV Transition Coalition was founded and is comprised of business, trade, industry and consumer groups, as well as grassroots organizations that share a vital interest in a smooth transition. The mission of the Coalition is to ensure that no consumer loses free full power over-the-air television reception in February 2009 due to a lack of information about the DTV transition. Today, more than 1,600 television stations nationwide already offer digital programming, so consumers in many markets are already enjoying the benefits of digital television, including crystal-clear programming, more channel choices and better sound quality.

Cable vs Broadcast

Broadcasters aren't alone in planning for HDTV. Companies that broadcast movies and events by satellite are also planning HDTV upgrades. Cable operators are also converting to digital, which will require new control boxes so that subscribers with analog TV sets can receive the new digital signals.

The good news for cable customers is that the digital transition should be easy. Thanks to a compromise adopted by the FCC in September 2007, cable companies will carry the main digital signal of “must carry” commercial full power broadcast TV stations and will duplicate that signal into analog format so that all channels can be viewed on any older analog TV sets connected to cable.

Cable’s carriage of the signals in both digital and analog formats will ensure that all customers will see commercial full power broadcast TV signals after the transition. This approach will make the digital transition effortless for all cable customers and provide valuable assistance to commercial TV stations trying to reach all of the homes in their region.

PSA Impact

The first and a very important issue for PSA producers is to decide if they will shoot their PSA in "Hi-Def," which for most producers is the approach they will use because of much better quality in the end result. Once that decision is made, however, it brings up other important issues such as the format for the master that will be provided to the dub house for replication. For guidance on how to submit your master materials for reproduction, go to: masterfiles.pdf.

For any organization that is using the Nielsen SIGMA electronic monitoring system to track their PSAs, the transition to HDTV will result in significant challenges.In anticipation of the digital conversion, Nielsen has developed encoding technology that will ensure detection of all encoded material in a digital-only environment.

However, the HDTV conversion will mean significant changes in PSA reporting because encoding facilities must use a new system of encoding TV tapes called SpotTrac, which replaces the analog code placed on TV PSA dubs. “Until all stations broadcast in HDTV, PSAs should be distributed to stations with both the analog and HDTV code, because some stations are converting early, and if the tape they receive does not have the HDTV code, they cannot be tracked by Nielsen,” Valerie Yoscak, of Video Labs Corporation observes . .

“In the months leading up to the HDTV conversion date, all PSAs should be distributed to stations with both the analog and HDTV code.”
Valerie Yoscak, Video Labs Corporation

Maintaining Station Call Letters

Beyond reporting, there are issues of station branding – stations have spent hundreds of thousands of dollars establishing a brand image in their communities that centered around their call letters. According to Nielsen, the station call letters you are used to seeing on SIGMA reports will remain the same, but how to handle sub-channels is going to present a much bigger challenge.

Since digital broadcast signals are sent as binary bits, that will free up some of the broadcast frequency spectrum for use by interests other than television. This means, among other things, there is no longer a one-to-one relationship between a frequency and a channel. In an HDTV environment, stations can provide multiple programming and data streams simultaneously. These multiple programming and data streams will permit up to six standard definition channels in what was previously a single broadcast channel.

Since most PSA distributors match their internal broadcast database to the Nielsen master list of stations, one of the biggest challenges will be to develop a standard station naming convention to permit station matching and accurate reporting. There is no current industry standard and no call letters currently assigned by the FCC. Accordingly, Nielsen will develop a system to give each digital sub-channel a unique set of call letters and clients or their distributors will then have to match the Nielsen master list. The situation is made more complicated by the fact that sub-channels are not required to carry the same programming, so the ultimate system that is developed must permit differentiation between stations and their sub-channels.

Other Monitoring Challenges

In order to provide a layer of backup monitoring during and after the digital conversion, Nielsen is converting its monitoring procedure for 900+ stations from over-the-air analog to a cable feed (just like the cable in your home). As stations begin to convert to digital, Nielsen will monitor both the new digital signal for both broadcast and cable TV.

During the HDTV transition, several things could impact future Sigma-based reports:

  • There are some stations for which the digital simulcast is currently not monitored. If these stations turn off their analog broadcast, data for this station will no longer appear in Sigma reports. Nielsen is adding equipment to monitor these stations.

  • There may be instances when an analog station is turned off within the Nielsen system before it actually converts. In this case, detections on the analog station are no longer reported and detections on the digital simulcast are reported under the analog call letters. Once the issue is corrected and Nielsen resumes monitoring the analog station, both stations will once again appear on Sigma reports.

  • Low power stations are not required to transition to a digital broadcast, but some may choose to change anyway. The digital simulcast of most low power stations is not currently monitored, and therefore these stations will not appear in Sigma reports.

Like many other major changes in the mass communications field, it may take some months to resolve all the issues presented by the conversion to HDTV but ultimately it will benefit content producers, the stations and viewers.

Resource Contacts:

For additional information about how Nielsen is handling the DTV transition, contact Anne Elliot, Vice President, Communications, The Nielsen Company at 813.366.3556

There is a special DTV Transition Coalition website at Also visit the FCC site at

Advantages of HDTV

Picture Clarity - Analog delivers 250,000 picture elements (pixels); HDTV provides two million. A conventional TV picture consists of 525 lines while the HDTV image offers 1,080 which will double the clarity of the picture. These additional lines mean that a viewer of a conventional TV set needs to sit 16 feet away before the lines disappear; for an HDTV viewer, they need only sit about six feet away to experience the same picture quality.

Wider Image - HDTV images are also 33 percent wider than traditional TV images, meaning the wider 16:9 aspect ratio enables viewers to see a third more of the action taking place in a sporting event, concert, movie or other program fare.

Enhanced Sound - HDTV provides viewers with CD-quality sound with up to five audio channels and a sixth sub-woofer channel to fill in the bass sound.

Multicasting - HDTV boosts the number of channels in a single transmission from one to five, permitting broadcasters to transmit much more information than was previously possible.

Datacasting - HDTV is also capable of delivering data, such as the Internet, hundreds of times faster than conventional modems. Datacasting could deliver services to the home ranging from bank and investment statements to customized traffic reports that show real-time images of a commuter's route to work.. It is estimated that HDTV could deliver both TV programming and eight major newspapers to the home in just 60 seconds.