Channel 4's Thursday night special on "Children and Divorce" won its half hour starting at 9 p.m. locally with a Nielsen rating (about 250,000 TV homes) and a 25 percent audience share . . .

According to a station spokesman, the program, hosted by Jim Vance, apparently posted the highest rating ever for a WRC-produced documentary . . .

Nationally, on Thursday night, the premiere of "Bridges to Cross" on CBS earned a 14.4 Nielsen rating and a 26 percent share . . . "Knots Landing" in the same 10 p.m. time slot for CBS a week earlier did an 18.4/32, by comparison . . .

Peter Hackes, one of the most familiar voices on network news over the past three decades, has turned in his trench coat . . .

He retired Friday after spending 30 years at the Washington bureau of NBC News. He had joined NBC after three years with CBS News . . .

During his tenure, Hackes reported on every presidential race, starting with President Eisenhower's 1956 campaign, and covered the Cuban Missile Crisis, the Watergate trials, the Three Mile Island nuclear plant disaster, the assassination attempt against President Reagan and the Air Florida crash in Washington, as well as regular assignments to the key White House, Pentagon and Capitol Hill beats . . .

NBC News President Lawrence Grossman said Friday that "Peter has been one of NBC News' most enduring, versatile and best-liked correspondents, who began by covering President Eisenhower and who is best remembered for his pioneering work covering the beginning of the space program. We salute him" . . .

Hackes, who is also a retired Naval Reserve captain -- and the father of "Entertainment Tonight" correspondent Peter Quinn Hackes -- plans to remain in the Washington area . . .

NBC News officially announced Friday that its oft-delayed magazine project, originally titled "American Almanac," will join the weekly primetime schedule on Tuesday, June 10, in the 10 p.m. time slot . . .

It will be called "1986," a last-minute title change following "Profile" and, until Thursday evening, "86/87" . . .

Roger Mudd and Connie Chung will anchor the revamped one-hour show . . . which was launched last August on a monthly basis, with the initial prospect that it would join the weekly schedule in January of this year . . .

Late in 1985, confronted by low ratings and a minimum of enthusiasm from TV critics, NBC News executives, as well as NBC Chairman Grant Tinker, had second and then third thoughts about the project . . .

Judged too slow-paced, and too "soft," for current primetime audience tastes, the show has since undergone several in-house test flights and former CBS News executive Bob Chandler (one of the developers of "60 Minutes") has been brought in to fine-tune the operation . . .

One reported conclusion: They'll need additional staff to meet a weekly magazine schedule . . .

By the way, Chung's new title as anchor (not coanchor) on "1986" is part of her new three-year contract, which she finally signed with NBC News on Friday . . .

She had been previously called "contributing correspondent" for "American Almanac"-"Profiles"-"86/87" . . .

In addition to the "1986" anchor job, Chung's assignments under the new contract include her continuing role as anchor of the Saturday night network news and primetime "News Digests" appearances when her schedule permits . . .

She has also been assigned to the "small group" of NBC News staffers who have been chosen to substitute for Tom Brokaw when he is not anchoring "NBC Nightly News" and also includes Roger Mudd, Garrick Utley, John Hart, John Palmer and Chris Wallace . . .

The new contract ends her association with "NBC News at Sunrise," which enjoyed a ratings rise on her watch . . .

Also in the News

And here's a list of the network correspondents who are attending President Reagan on his current 13-day trip to the Orient and Southeast Asia . . .

None of the anchors is gracing this trip, in part because of budget considerations, in part because the networks are guessing not much "news" will emanate from the "economic summit" . . .

For ABC, it will be White House correspondents Sam Donaldson, Sheilah Kast and Kenneth Walker; chief foreign correspondent Pierre Salinger; and chief Asia correspondent Jim Laurie. Total crew: about 64 . . .

For CBS: White House correspondents Bill Plante, Lesley Stahl, Jacqueline Adams and Gary Schuster plus State Department correspondent Deborah Potter. They'll be joined in Tokyo by Barry Petersen and David Jackson, plus Terry Smith for "CBS Morning News." Total crew: "about 60 people" . . .

For NBC: White House correspondents Chris Wallace, Andrea Mitchell and Robin Lloyd (who will cover Mrs. Reagan); Bob Jamieson for "Today"; and economic correspondent Irving R. Levine. They'll be joined by Keith Miller from the Tokyo bureau. Total crew: "about 50 people" . . .

For Cable News Network: White House correspondents Charles Bierbauer and Frank Sesno, foreign affairs correspondent Ralph Begleiter, financial correspondent Ed Atwood, correspondent Tom Mintier and Tokyo bureau chief Mark Dulmage. Total crew: About 40 people . . .

A little more out of that meeting last week between A.C. Nielsen and local TV station executives . . . who have complained that the ratings sample is not truly reflective of the Washington market . . .

They've complained that Nielsen is "oversampling" the 55-plus audience and "undersampling" the 35-and-unders, a sample which, they contend, favors Channel 9 in the ratings . . .

According to one participant, Nielsen has agreed to "oversample" the younger audience during the May ratings sweeps and will, by the November ratings sweeps, increase the "working total" of local meters from 400 to 450 (a certain percentage of meters installed on local TV sets are always out of service) . . .

ABC Entertainment announced Friday that "The Ellen Burstyn Show" will be somewhere on the network's fall schedule . . .

The Oscar-winning actress (for "Alice Doesn't Live Here Anymore") plays "a witty iconoclastic college professor who thrives on her independence even though she, her mother, divorced 25-year-old daughter and grandson share the same house." The Walt Disney TV production was accepted after a look at the pilot . . .

Some 400 Public Broadcasting Service station managers and local board members are in town for the annual joint meeting of PBS and the National Association of Public Television Stations . . . which runs through Wednesday . . .

Highlights of today's meeting: a seminar on the burning issue of "enhanced underwriting" for the financially troubled public system . . . and a luncheon hosted by Project Literacy U.S., a joint public service program on adult illiteracy of PBS and Capital Cities/ABC Inc. Labor Secretary William E. Brock will address the meeting luncheon . . .

Among the six new members joining the 35-member PBS board of directors this session will be E. William Henry, chairman of the WETA board . . .

Tomorrow, at the NAPTS meeting, they'll hear from Rep. John D. Dingell (D-Mich.), chairman of the House Energy and Commerce Committee, FCC Commissioner James H. Quello and Sen. Lowell P. Weicker (R-Conn.). A hot topic: the "must-carry rules" agreement between broadcasters and cable operators that could bar public TV stations from many cable systems around the country . . .

Tomorrow night, the annual membership banquet will feature "A Prairie Home Companion" host Garrison Keillor . . .

On Friday, NAPTS filed its objection to the "must-carry" agreement with the Federal Communications Commission, which plans a review of the National Association of Broadcasters-National Cable Television Association deal . . .

And Finally

A video pirate calling himself "Captain Midnight" (no relation) struck at midnight in the Chicago area Saturday, breaking into a Home Box Office airing of "The Falcon and the Snowman" with a nationwide protest against scrambling of satellite transmissions . . .

A multicolor test pattern and a five-line message printed in white letters read: "Good evening HBO from Captain Midnight. $12.95/month. No way. Showtime/Movie Channel beware" . . .

HBO's authorized signal was replaced for anywhere from 10 seconds to more than a minute in Chicago and on the East Coast. The message appeared at 10 p.m. Saturday on the West Coast . . .

HBO had no comment yesterday but officials of Cablevision, a Chicago-area cable marketing firm, notified the FCC . . .

The $12.95 reference in the message apparently was to the subscription fee now required of many viewers who had been watching free of charge by using their own dish antennas. HBO recently began scrambling its signal . . .

Speculation was that the pirate may have been able to overpower authorized signals beaming down from a satellite. Which means Captain Midnight could conceivably also strike CBS, NBC or even NASA . . .