THE COMMUNICATIONS business should be governed more by the marketplace and less by the FCC. That is what Charles D. Ferris, chairman of the Federal Communications Commission, has been emphasizing in his first major policy speeches. He "will rely on competition instead of rules whenever that is promising or possible," Mr. Ferris told the National Association of Broadcasters last month. In particular, he wants to "encourage new technology and services." Broadcasters, he said, will have to sustain their profits, and their place in American homes, by offering more diverse programing, more community services and new means of channeling information through television sets.

In blunter terms, Mr. Ferris told the National Cable Television Association last week that if cable does not fulfill its promises of innovation, "it may be bypassed in the marketplace by those who do." That must have jarred his audience a bit. As Mr. Ferris noted, the cable industry was constrained for years by regulatory policies that often favored broadcasters and telephone companies. Now, fresh from major victories in Congress and the courts, the cable operators had been looking forward to a better reception at the FCC. Instead, the chairman wants to encourage a new generation of competitors.

Mr. Ferris, a newcomer to communications fields, has evidently not been captured by the established interests there. If anything, he is captivated by technology and the potentiality of satellites, computers, two-day cables, home video systems and the like. There is good reason to be bullish on electronics these days. Home video recorders are growing less expensive and more popular. Home computers are approaching the mass marketplace. In Columbus, Ohio, Warner Cable is trying out a two-way cable system called Qube; in Great Britain, advanced networks for transmitting data are already in use.

In general, national communications policies have lagged behind this hurtling technology. As in the case of cable, each new entrant has had to battle for a fair place in regulatory schemes set up when broadcasting, telephones and other older-line industries were young. One central question now, therefore, is whether regulation should be modernized to take in new technologies, or eased substantially. This is the point on which we find Mr. Ferris's views most interesting and eencouraging. He does not want the FCC to dictate future communications system and services. Instead, he thinks the "public interest" should be defined, to a greater extent, by what the public is actually interested in buying and subscribing to - in short, by competition in the marketplace.

Of course, stating that view is easier than spelling it out in regulatory decisions - or selling it to the consumer groups, as well as industries, who have come to rely so heavily on the FCC. We hope, though, that Mr. Ferris will persevere. In our view, he has set out on a creative course.