CBS Entertainment announced its fall primetime schedule yesterday, a major realignment that leaves only the Sunday nights lineup intact . . .

Seven new series -- including four half-hour comedies and three one-hour dramas -- will be introduced, while 10 holdover series will get new time slots . . .

The network also took pains to announce that "a new Mary Tyler Moore series is being prepared for future broadcast" . . .

Gone from the current schedule will be several short-run series like "Morningstar/Eveningstar," "Bridges to Cross," and "Leo & Liz in Beverly Hills" as well as the Wednesday night movie, "Charlie & Co.," "Airwolf" and "Crazy Like a Fox" . . .

During the "official" 1985-86 primetime season just concluded, CBS finished second behind NBC . . .

However, CBS won Monday, Friday and Sunday nights, despite general weakness in the key 8-to-9 p.m. time slot (which can determine audience size for the entire evening) and its failure to launch a single successful new sitcom during a season in which comedy was king on NBC and at least a prince of the realm on third-place ABC . . .

Next fall's nightly schedule (N indicates new, NT indicates new time period), starting with:

Monday: 8 Kate & Allie (NT); 8:30 Taking the Town (N); 9 Newhart (NT); 9:30 Designing Women (N); 10 Cagney & Lacey . . .

Tuesday: 8 The Wizard of Elm Street (N); 9 CBS Tuesday Night Movie . . .

Wednesday: 8 Together We Stand (N); 8:30 Better Days (N); 9 Magnum, P.I. (NT); 10 The Equalizer . . .

Thursday: 8 Simon & Simon (NT); 9 Knots Landing (NT); 10 Kay O'Brien, Surgeon (N) . . .

Friday: 8 Scarecrow and Mrs. King (NT); 9 Dallas; 10 Falcon Crest . . .

Saturday: 8 Downtown (N); 9 Mickey Spillane's Mike Hammer (NT); 10 The Twilight Zone (NT) . . .

Sunday: 7 60 Minutes; 8 Murder, She Wrote; 9 CBS Sunday Night Movie . . .

"Taking the Town" stars Pam Dawber as a "bright, independent, free-lance photographer living and working in San Francisco whose active social and professional lives are complicated by the arrival of her irrepressible, high-spirited teen-age sister (Rebecca Schaeffer)" . . .

"Designing Women" stars Delta Burke, Dixie Carter, Annie Potts and Jean Smart in "a comedy about four very different women and their fledgling decorating business" . . .

"The Wizard of Elm Street" is a fantasy-adventure starring David Rappaport as Simon MacKay, who calls himself a toymaker and "delights children and adults alike with his fantastic contraptions, although certain foreign powers also seek his incredible skills -- and not always for humane reasons." Simon's prote'ge' is a precocious teen-ager (Billy Jacoby). Two disparate government agents are assigned to watch over him . . .

"Together We Stand" stars Elliott Gould, Dee Wallace Stone and Key Huy Quan in the story of a couple who adopt "an eager-to-please Asian-American teen-ager" and his "black, precocious and adorable" 6-year-old "sister" . . . to join their adopted daughter Amy and their natural son Jack . . .

"Better Days" stars Raphael Sbarge and Dick O'Neill in a comedy about a "fun-loving Beverly Hills lad who must move to Brooklyn and live in an apartment above a fruit stand owned by his grandfather." The only white player on the high school basketball team, he quickly befriends two black teammates, "menacing Luther and fast-talking Snake" . . .

"Kay O'Brien, Surgeon" stars Patricia Kalember in a drama about a 28-year-old second-year surgical resident, nicknamed Kayo. Her New York hospital confreres include a resident "who does his arrogant best to prove that women have no place in surgery," a sarcastic chief surgeon ("who appears to have an unspoken admiration for Kayo's work") and a senior resident who sleeps in a hospital linen closet . . .

"Downtown" is a "police drama with humor" starring Michael Nouri as a "tough Los Angeles cop who has stepped out of bounds one time too many" and has been made a supervisor of four "colorful" parolees . . .

Also in the News

Part III of "North and South: Book II" Tuesday, which took a half-hour slide in the schedule because of President Reagan's last-minute decision to address the nation, registered a 21.6 national Nielsen rating and a 36 percent audience share . . .

Locally, "North and South" registered a very large 26.9 Nielsen count and a 44 percent audience share on Channel 7 . . . as the mini-series continues to be a Washington favorite . . .

CBS News joke: What's the new title for "1986"? . . .

"June" . . .

Channel 5 yesterday announced that it will carry four Redskins exhibition games this summer starting with the Aug. 10 match at New England Patriots at 7 p.m.; Aug. 15, the Pittsburgh Steelers here at 8 p.m.; Aug. 23 at Tampa Bay Buccaneers at 7 p.m.; and Aug. 29, the Atlanta Falcons here at 8 p.m. . . .

Johnny Carson couldn't be at the Plaza in New York yesterday to receive his George Foster Peabody Award but he showed up via satellite walking on the grounds of his Malibu home, clad in a sports shirt and sneakers, with a stick in his hand as he explained he was "just checking the radioactivity" . . .

He said the fallout from the Soviet Union has improved the air quality in Los Angeles . . .

Carson told the Peabody audience that he was "very flattered and extremely happy" about his selection. "If there's one fond wish of an entertainer or someone in the communications business, it has to be that someone appreciates that you're bringing a certain quality to your work and likes what you do." In his acceptance speech, he made no mention of the defection of Joan Rivers from NBC to the new Fox Broadcasting Co. . . .

The Peabody award recognized "the contribution Johnny has made to television, to humor and to America" . . .

Said Carson: "I've always wanted to attend an awards luncheon in the Plaza wearing Reeboks and a sport shirt" . . .

Daily ratings for "The MacNeil/Lehrer NewsHour" on PBS for the October 1985-February 1986 period rose 27 percent over a similar period a year ago . . .

Before you run out and sell your stock in "CBS Evening News With Dan Rather," however, you should realize that the jump represents an increase in the Nielsen ratings from a 1.5 and a 3 percent audience share to a 1.9/4 . . . or stated another way, an increase from 1.2 million TV homes to 1.6 million . . . out of a possible 85.9 million TV homes . . .