A Radio Listener With A Million Ears

They may be invisible, but the airwaves are getting awfully crowded. There are so many radio and television stations on the air now that advertisers have trouble verifying that their spots run as scheduled. Likewise, record companies have no easy way to tell which radio stations are playing their songs, and when. A high-tech solution that's catching on comes from Broadcast Data Systems, a unit of Affiliated Publications Inc., which publishes Adweek and Billboard.

Broadcast Data's receivers and computers in the top 83 media markets continuously scan local airwaves and identify what's on using pattern-recognition techniques. The samples are sent by phone to Kansas City, Mo., where a mainframe matches them against data on some 200,000 songs and commercials. Computer-generated reports are sent to clients, such as Warner Bros., which pay $175 and up per week. The Clinton and Bush campaigns both used the service, too, to verify their own ads and to monitor each other's.