On the screen a player piano was playing and an old model steam engine was clanking away. The announcer, in an unmistakably British accent, was explaining how the old machines illustrate different points about the way social groups operate.

"I had a hard time understanding everything," said Ed Walls, who is enrolled this fall at the University of Maryland in a course that uses television to help in the instruction. "But when they actually showed me the steam engine [on the TV film] it helped me understand what a 'closed loop' was . . . . In a course like this, you have to be a lot more disciplined to do well than you do in regular classes. But you get some things a lot easier because they can show them to you."

Walls, 43, a warrant officer at Fort Meade, is participating in the country's first national system of television-assisted college courses leading to a bachelor's degree.

The project, whose headquarters is in a cluttered office in College Park, has been launched as a joint venture by the University of Maryland and the Maryland Center for Public Broadcasting. It uses mostly courses and television shows produced by the British Open University and the British Broadcasting Corp.

This fall, the venture is starting with a $400,000 grant from the Carnegie Corp., seven affiliated colleges and 10 educational television stations or statewide networks from Vermont to Los Angeles.

All the programs can be watched by the students at home, although sometimes the TV films also are shown in class. Locally, the programs are broadcast Saturdays on Channel 22 in Annapolis.

Enrollment in the three TV-assisted courses this fall is just 390 students nationwide, including 240 at the University of Maryland.

"We have to crawl before we can walk," said Frederick Breitenfeld, executive director of the Maryland Center for Public Broadcasting. "I'd put my own money on it that there are people out there who want these types of programs."

So far, however, televisioin has had only a minor impact on American higher education even though scattered colleges around the country have been producing television, courses since the early 1950s. "There have been a lot of professors out there laying on narcotic stuff," Breitenfeld said. "Of course, not many people have been watching.

"In England, the Open University has been an enormous success," he continued. "It's high intellectual rigor stuff, and I think it's going to attract adults who have trouble driving to class after a long day but are ready to bear down and spend the time studying. Let history tell. I think there are people out there who are interested."

Each of the British-made courses runs 16 to 18 weeks, carries nine credits -- triple the amount of the standard American college course -- and requires 15 to 20 hours of study per week. There are nine half-hour television shows for each course that are supposed to "pace and stimulate" the students, said Adele Seef, assistant director of the program at the University of Maryland. "But they really are only supplemental," she said, "to a very heavy print package."

In the systems management course that Walls is taking, there are six required texts, four written assignments and two examinations. In the television shows that are part of the course, instructors teach basic concepts, using film clips of different examples that could never be brought into a classroom. For instance, to show the idea of "intermittent feedback," the film shows footage of a driver cruising along a highway with a helmet that covers his eyes for different periods of time.

The television shows for the Roman history course are considerably more elaborate and have the gloss of TV documentaries. In one, an archeologist shows off the excavations of Roman baths and villas that he helped uncover in southern Britain.

In another, which is accompanied by organ music and choirs, a film crew and several professors visit a Roman cemetery underneath St. Peter's basilica in Rome. For part of the show, one professor sits on top of an ancient tomb, his legs dangling over the side as he explains the archeological detective work involved in finding the possible grave of St. Peter.

"I think it's a mistake to call what we're doing a television university," Seef said. "But television offers an enrichment -- a dimension you can get no other way. The visual impact is a very important part of the course."

The seven colleges offering the courses this fall include Maryland, Penn State and lesser-known institutions such as Iona College in New York and Linfield College in Oregon. All of them run discussioin groups called "learning centers" that students can attend voluntarily, usually once a week.

The tutors who lead these groups also grade essays and exams. But they are not allowed to add anything to material covered in the television films, assigned readings and study guides, which are written in a chatty, informal style by British academics.

Each college gives its own credits for the courses and charges its own fees, which come to $369 for a nine-credit course at Maryland.

The project's founders have given it the rather grandiose name, National University Consortium for Telecommunications in Teaching, and even though enrollment is relatively small, they hope to add 20 more colleges and television stations next fall and 30 more the year after.

Although the Maryland-based project has just started broadcasting its courses, it already faces competition. The Public Broadcasting System has established PTV-3, an educational service, and announced plans to begin college-level courses next fall. The University of Mid-American, a grouping of 11 Midwestern colleges based in Lincoln, Neb., wants to do the same thing, giving its own credits and exams throughout the country.

In the wings there is an offer by Walter H. Annenberg, publisher of TV Guide and former U.S. ambassador to Great Britain, to give $150 million for college-level courses to the Corporation for Public Broadcasting. In turn, the corporation would make grants to television producers and colleges.

Despite the competition, there is considerable skepticism that any of the college television projects will amount to very much.

"So far television has been marginal, very marginal at American colleges," said Irving J. Spitzberg Jr., general secretary of the American Association of University Professors. "And I think it's likely to stay that way . . . . I think it's terribly ill-times to try something more now as we enter the '80s with declining enrollments. The [existing] institutions themselves are looking for students. If something first-rate develops on television, many [colleges] would see it as a vampire, sucking their life blood, and they would resist."

According to a study by the Corporation for Public Broadcasting and the National Center for Education Statistics, 735 colleges offered a total of 6,884 courses over television in 1978-79, enrolling an estimated 498,200 students. But these TV courses accounted for only about 1 percent of all credit hours taken at American colleges, according to estimates by the Education Statistics Center.

Richard W. Smith, director of development projects at the Maryland Center for Public Broadcasting, said the TV-assisted courses have done well in Maryland, because they are part of an Open University program that has been running for eight years.

"But the whole [national] consortium arrangement is very difficult to mount," he said. "TV stations and universities are on different time frames. For television six weeks is a long time for scheduling ahead. Six months is a short time for a university to schedule a new course . . . . Meshing the two has made it hard to get [student] registrations."

Another problem, he said, may be the courses. Two of the three being presented this fall were produced by the British Open University -- the history of the Roman Empire and the course on systems management.

Even though the courses have attracted about 200,000 students in Britain and produced 39,000 university graduates there since starting in 1971, "they are fairly difficult by American standards," Smith said, "and that may be discouraging."

This fall the coast-to-coast program includes just one American-made course -- introduction to mathematics. Smith said it was produced by the Maryland Center for Public Broadcasting because the comparable British course was "just too damn difficult for Americans."

The center and the University of Maryland have just finished producing another course in basic English composition, which will be given next spring. It was needed, Smith said, because the American students "have difficulty with all the essaywriting that the British courses require."

Over the next few years the TV project hopes to produce more courses of its own and eventually have American courses only, Breitenfeld said.

"That costs a lot of money," he said. "The British are now spending more than a million dollars a course . . . . But we figured, 'We have the British courses now and the alternative is doing nothing, so let's go,' and we did it."