3 STUDIOS TO BUY SHARES IN A PAY-TV NETWORK

Trying again to win a larger portion of pay television's growing revenues, some of Hollywood's largest studios announced plans yesterday to become partners in an all-movie pay-television network.

The studios - Paramount Pictures, MCA Inc. and Warner Brothers - agreed to buy equal shares in the Movie Channel, a 24-hour cable network that reaches more than two million subscribers. The network is owned by Warner-Amex Satellite Entertainment, a 50-50 venture of American Express and Warner Communications, the parent of Warner Brothers.

Under the agreement, the three movie studios will be equal partners in the network, while American Express will hold a smaller share, which has not been specified yet. Each of the studios is expected to pay about $25 million for its share of the service, according to a studio executive involved in the negotiations.

The transaction marks the second time in two years that major studios have tried to build an effective competitor to Home Box Office, which is by far the largest pay-television network, with more than 10 million subscribers.

Home Box Office, owned by Time Inc., is expected to gross more than $500 million in revenues this year from its fare of movies, specials and sports. That is well behind Time's magazine division, which grossed $870 million last year, but HBO is the company's fastestgrowing operation. Time Inc. had gross revenues of $3.3 billion last year.

Another major movie studio, 20th Century-Fox, has reportedly been in serious talks to buy a large share in Showtime, which is the second-largest pay-television service, with 3.5 million subscribers. Showtime is owned by Viacom, which has made public its interest in finding a partner.