DIGITAL RADIO PORTENDS CLARITY AND UNCERTAINTY

You could say radio's future is already here. Digital audio broadcast (DAB) produces the kind of clarity that audiophiles once only dreamed of. Broadcast by satellite, DAB does away with static interference and costly transmitters and repeaters. While it's now available in Japan and parts of Europe, neither the market nor the political climate appears ready for it.

In Japan, DAB was introduced in 1992. At the time, the special tuner required to convert the satellite signals to sound cost up to $2,300. Prices have dropped, but not quickly enough to create a vibrant market for the service. By the summer of 1993, two of the original six providers of digital satellite radio had quit the business, and mergers have since shrunk the market to two companies.

"The merits of digital satellite radio are just the quality of the sound," says an official of Japan's Posts and Telecommunications Industry, noting that Japanese consumers are much more taken with another new development: visual radio.

Digital compression now allows text to be sent along the airwaves with sound. For $250, Japanese can buy a "smaller than a shirt pocket" visual radio that, with the push of a button, will identify the song being played. Press again, and there's the traffic and weather. No more waiting for "10 past the hour" for updates.

When the cost of digital receivers goes down even further, DAB is expected to catch on as quickly as visual radio. But there's also a political stumbling block.

While most of the world has already agreed to use a digital system called Eureka 147, which was pioneered by a European-based consortium, broadcasters in the United States are balking. They support an alternative system known as IBOC (In Band On Channel), which allows broadcasters to use their current radio spectrum to deliver digital sound.

Since many countries are already going ahead with Eureka, analysts predict that the US may be the last place that radio's digital revolution takes hold.