NBC, the reigning primetime champion, yesterday announced a 1986 fall schedule that features eight new series: four one-hour dramas, three half-hour sitcoms and "1986," the one-hour newsmagazine anchored by Roger Mudd and Connie Chung . . .

In all, NBC is introducing 6 1/2 hours of new programming, matching third-place ABC's total for next fall. Earlier, CBS announced five hours of new shows . . .

In addition, the network moved nine holdover series to new time slots. "Miami Vice," for instance, will be up against CBS' "Dallas" at 9 p.m. Fridays . . .

Tuesday, Friday and Sunday nights, which were owned last season by ABC, CBS and CBS, respectively, were targeted for major overhauls . . . and the 13 half-hour comedies on the new schedule will be the most ever for NBC . . .

On Wednesday, another weak spot in the NBC schedule, the network will pit "Gimme a Break" and "You Again" in the 9-to-10 time slot against ABC's powerful "Dynasty" and CBS' choice of "Magnum, P.I." . . .

Sent packing by NBC were "Punky Brewster," "Remington Steele," "Knight Rider" and "Silver Spoons," as well as newcomers "Blacke's Magic," "Last Precinct," "Stingray" and "Alfred Hitchcock Presents" . . .

Here's the fall NBC lineup (N indicates new show, NT a new time period):

Monday: 8 ALF (N); 8:30 Amazing Stories (NT); 9 NBC Monday Night at the Movies . . .

Tuesday: 8 Matlock (N); 9 Crime Story (N); 10 1986 (N) . . .

Wednesday: 8 Highway to Heaven; 9 Gimme a Break (NT); 9:30 You Again (NT); 10 St. Elsewhere . . .

Thursday: 8 The Cosby Show; 8:30 Family Ties; 9 Cheers; 9:30 Night Court; 10 Hill Street Blues . . .

Friday: 8 The A-Team (NT); 9 Miami Vice (NT); 10 L.A. Law (N) . . .

Saturday: 8 Facts of Life (NT); 8:30 227 (NT); 9 The Golden Girls; 9:30 Amen (N); 10 Hunter (NT) . . .

Sunday: 7 Our House (N); 8 Easy Street (N); 8:30 Valerie (NT); 9 NBC Sunday Night at the Movies . . .

As for the new programs, "ALF" stars Max Wright as "an ordinary guy caught up in something extraordinary when an Alien Life Force lands with his space vehicle on his garage" and moves in with the family. ALF is played by a furry puppet. This show has good ancestry . . .

"Matlock" stars Andy Griffith as "the sharp and charming Atlanta lawyer Ben Matlock." Dynamite as an NBC pilot last March . . .

"Crime Story" is a police-action drama from Michael Mann, the "Miami Vice" executive producer, and deals with "the Major Crime Unit, an elite squad of Chicago detectives in the 1980s." Stars Dennis Farina, Stephen Lang and Anthony Denison . . .

"1986" with Mudd and Chung is described by NBC as a "distinctive prime time news hour." Ed Rable and Lucky Severson are regular correspondents . . .

"L.A. Law." This is the series Steve Bochco took when he was dismissed from "Hill Street Blues." Series is about "what goes on in a bustling Los Angeles law office, and how it affects the lawyers and their clients is the continuing theme." Stars Harry Hamlin, Jill Eikenberry and Richard Dysart. Series' biggest problem: This is a favorite project of NBC Chairman Grant Tinker, and he's a tough audience . . .

"Amen" stars Sherman Hemsley and Clifton Davis as "a Philadelphia Deacon who meets his match when a new minister arrives on the scene" . . .

"Our House" stars Wilford Brimley as an "outspoken retiree who loves his privacy" but takes his recently widowed daughter-in-law and three grandchildren under his roof. This show and "Easy Street" were NBC's highest tested comedy pilots . . . with Brimley "the highest testing lead ever to be in an NBC series pilot" . . .

"Easy Street" stars Loni Anderson as a "young widow after only one year of marriage, who is left heir to a large fortune and estate." To keep her company, she brings home "her snarly old uncle" and one of his raffish cronies . . . upsetting the snobs in the family. Do snarls make it on Sunday night? . . . Just Wondering

What if Pam has just been having a real bad dream all season long on "Dallas"? . . .

Will somebody please look outside and check if the moon is full? Or at least blue? . . .

The TV hoax count went up to three yesterday as both ABC News and NBC News admitted on the air last night they had unwittingly shown fake pictures of the Chernobyl nuclear site Monday night . . . and ABC Entertainment's "Good Morning America" admitted they had been taken in by "Joe Bones" and his six commandos from the "Fat Squad" Tuesday morning . . .

On the air last night, "ABC World News Tonight" anchor Peter Jennings was scheduled to say, in part: ". . . We can sum it up fairly quickly. We were the victims of fraud. This is some of the footage we purchased from a Yugoslav who we believed at the time had been visiting the Chernobyl area when the accident occurred, who had taken his camera and taken these pictures. He had taken his camera all right, but when the video showed up on Italian television (it was also on NBC), some sharp-eyed Italian suggested the pictures were really of Trieste, in Italy. In cooperation with the Italian police, we made an intense investigation, and yes, the video had been taken at Trieste. We were badly misled. We misled you, and we're not very happy about that" . . .

NBC issued a statement that said in part: ". . . Yesterday, Italian television raised some doubts as to the authenticity of the tape and said the pictures were actually taken in Trieste. Together with the Italian police, we have thoroughly investigated the incident. The unfortunate conclusion is that NBC News was the victim of fraud. We regret the incident" . . .

Meanwhile, neither ABC nor NBC has forwarded their checks for $11,000 to the alleged perpetrator, who claimed to be a Yugoslav tourist visiting the Soviet city the day after the blast . . . The pictures were apparently of a recent cement factory fire in Trieste . . .

CBS News, dubious about the source of the film from the start, never did make a bid on the footage . . .

Dan Rather reported last night on the "CBS Evening News" that a 24-year-old Frenchman, whom he didn't identify, had been arrested in Italy in connection with the hoax . . .

Meanwhile, over at "Good Morning America," Executive Producer Philly McGrady, like a lot of readers, spotted "an offbeat and different" story in The Philadelphia Inquirer over the weekend about "The Fat Squad," the newest fad in dieting. For $300 a day, the story went, the Squad would go into your home and physically restrain you from eating . . .

After reaching "Joe Bones," the head of the Fat Squad, Monday morning, "GMA" contacted a woman he directed them to, who confirmed that the Squad had done a "terrific" job for her. On the basis of her endorsement, "GMA" booked the Squad . . .

So, as the last segment on Tuesday morning, there was Joe Bones, head of the Fat Squad and six of his commandos -- wearing their dark glasses as enforcers of something called the Rambo Diet . . .

Bones told host David Hartman how his Fat Squad frisked husbands for contraband food as they returned from the bathroom and tackled wives when they went for the refrigerator (their client contracts empowered them to use violence when necessary) . . .

But Joe Bones was really Joe Skaggs, a world class hoaxer, who'd already conned papers like The Washington Post, The Miami Herald, the New York Daily News and others with his Fat Squad fabrication (see story on Page C2) . . .

McGrady said yesterday, "We received dozens of serious inquiries about the diet" after the show was over and before someone finally realized that Joe Bones had been on the show before, urging condominiums for fish, and that it was probably a hoax. Hartman concluded yesterday's broadcast by admitting with a smile they'd been had . . .

"We got taken," said McGrady, who added that at "GMA" they're calling it "the Fake Squad" . . .

CBS' movie "Second Serve," about the male Yale grad who decided to become a lady tennis player (has anybody checked that full moon, yet?), attracted only a 13.6 national Nielsen rating and a 22 percent audience share Tuesday night . . .

The Joe Piscopo musical/comedy special on ABC did only a 12.7/22 at 10 p.m., but a strong showing from its sitcoms and "Moonlighting" earlier in the evening enabled ABC to win the night . . .

ABC Entertainment President Brandon Stoddard, who is almost as funny as NBC Entertainment President Brandon Tartikoff, tried out a couple of bons mots Tuesday night when he met in New York with advertisers to discuss the fall schedule . . .

"There are more people in this auditorium tonight than watched our entire Thursday night lineup last season," said Stoddard . . .

Referring to tightfisted Capital Cities/ABC Inc. Chairman Tom Murphy's pledge to make a "major commitment" to primetime programming next fall, Stoddard said, "We're putting on nine new programs. That's a major commitment. However, they're only letting us buy one episode of each show and we'll have 51 weeks of repeats" (On second thought, Captain Airwaves thinks maybe we all had to have been there) . . .