When an estimated 15,000 cable operators and programmers gather Sunday in San Francisco for the 42nd annual National Cable Television Assn. confab, don’t be surprised if the party hats and streamers remain tucked safely out of sight.

After all, this is an industry still in mourning over passage of the cable reregulation bill in Congress last year. The worst is yet to come: Cablers are faced with Federal Communications Commission rules requiring them to roll back rates as much as 15% to customers.

Adding to industry woes is the prospect of ugly retransmission consent talks with broadcasters in coming months. Broadcasters and cablers appear headed on a collision course over retrans payments beingdemanded by TV stations.

Despite the Washington woes of the past and the broadcast industry battles of the future, cable exex are bullish in at least one area: technology. Perhaps that’s why NCTA, which runs Sunday through Wednesday, has selected as its convention theme “America’s Highway to Tomorrow.”

Cablers believe they have a leg up on competitors in the race to build America’s “information superhighway,” says Richard Roberts, prez of Norfolk, Va.-based TeleCable Corp. and the new NCTA board chairman. “Cable TV is the only broad-band high-capacity communications system in place right now,” he says.

The technological emphasis will be the common thread running through NCTA ’93 .

Monday’s opening session, which will be moderated by ABC’s Jeff Greenfield, will feature a discussion of the electronic superhighway by such industry heavyweights as John Malone, head of Tele-Communications Inc.; Viacom prez Frank Biondi; Jim Clark, chairman of Silicon Graphics; and Cablevision Systems chieftain Charles Dolan. “Star Wars” creator George Lucas also will speak at the session.

Wednesday’s closing event, “Mapping the Highway: Cable’s Telecommunications Future,” will again feature Greenfield as moderator. Participants in the discussion will include Time Warner Cable CEO Joseph Collins, Discovery Communications head John Hendricks and Comcast Corp. topper Brian Roberts.

Interim FCC chair James Quello will speak at a Tuesday luncheon. FCC commish Ervin Duggan will speak at a panel discussion on “Building the National Telecommunications Infrastructure.”