Television is one of the most pervasive forms of communication and one of the most influential and visible forms of popular culture. Some researchers believe that the mass communication capability of television has increased cultural homogeneity in all but a very few places. This paper contends that the American, National, and Columbia Broadcasting networks (ABC, NBC, and CBS) present enough variation in programming to permit television to be a variable, not homogeneous, mass medium. Differences also occur in the number of television channel choices available in individual homes. None of these three networks provides complete national programming delivery, and some geographic areas receive programming from only one or two of the three networks. A difference exists in the broadcast range between Ultra High Frequency (UHF) and Very High Frequency (VHF) stations, and local stations may consciously delete selected programs. Program content analysis and audience surveys are needed to determine if variations in communication patterns produce a diversity in U.S. popular culture. Nine references, four tables, and three maps are included. (JHP)