A major change in how the Mutual Radio Network delivers its news and sports programming was announced this week by Westwood One/Mutual Broadcasting System Inc. Starting March 10, Mutual plans to add a fourth newscast per hour and begin doing five sportscasts during morning and afternoon drive slots.

The changes, according to Mutual, which bases its news operation in Arlington, were prompted by a national listener survey that suggested in part that the news should be "fresh and frequently updated."

Ron Nessen, vice president of news and special programs, said, "We found that programmers want choices -- in the broadcast clock, in the lengths of newscasts and in how the news is presented."

In addition, Mutual has added more segments of "Lasorda at Large," by Los Angeles Dodgers Manager Tommy Lasorda, and also "Larry King: Sports in Focus," by the talkmeister whose nightly guest show is now beginning at 11 p.m. The local affiliates of Mutual are WTOP-AM (1500), WGMS-AM/FM (570/103.5) and WINX-AM (1600). Holland Cooke, operations manager at WTOP, said the changes wouldn't affect the all-news outlet that much because "we graze at the salad bar of news" from Associated Press, CBS, Mutual and its own staff. Pierre Eaton, the general manager of WINX, said the changes only affect them on the weekend. "In the sports schedule we have to readjust four of the times we carry Mutual Sports because they have either kicked them off or changed the times." Love Notes

In case you need last-minute inspiration in words or music -- Larry Matthews of WMAL-AM (630) is doing a "love stories" series today at 9:15 a.m., 12:50 p.m. and 5:20 p.m; "Tempo" at 10 a.m. on WGMS will feature "Romeo and Juliet" by Prokofiev, Tchaikovsky and Berlioz; WHUR-FM (96.3) and WWRC-AM (980) are playing love songs all day; WPFW-FM (89.3) is hosting "The Love Game," a special call-in segment on love and friendship. Mary Drayton and Owen Scott will host from 1:30 to 3 p.m. . . . WRQX-FM (107.3) is inviting its listeners to a bash at the Sheraton Potomac tonight from 7 to 11 p.m. with Jim Elliott, Sandy Weaver, Gary Spears and Chris Jagger, who will be doing a remote broadcast. Playwright Honors

The Children's Radio Theatre announced this week that the second and third graders of P.E. Williams Elementary School in Upper Marlboro are one group of winners of the annual Henny Penny Playwriting Contest. "Mercury, the Fastest Kid in Town," the Williams play, was cited by the judges and will be produced April 12 at the Kennedy Center and aired over WPFW-FM (89.3). Personnel Notes

WRQX this week moved Vinny Brown, its late-night personality, to the vacation relief and weekend shift. A statement released by Program Director Randy Lane said, "Q-107 is allowing Vinny Brown to pursue other career advancement opportunities. Although these opportunities do not present themselves at Q-107 in the foreseeable future, Vinny will remain with the station in an auxiliary position." Paul Fuller, the new music director, is taking over the 10 p.m. to 2 a.m. shift, which ranks seventh in the market, according to Arbitron ratings . . . Rona Barrett, whose reports on the entertainment world are heard on WTOP, has renewed her contract with Westwood/Mutual. In addition to her daily news reports, Barrett will be doing four hour-long specials in the next year . . . Lauri Butler, previously a news reporter in Hartford, Conn., has joined WCLY-FM (95.5) as morning anchor . . . WCXR-FM (105.9) has hired three new people: Bob Brooks from WGRX in Baltimore for its 3 to 7 p.m. shift; Kevin Malvey, also from WGRX, for its early morning show with newsman Paul Wagner; Doug Gondek from KSTM in Phoenix to do the 10 a.m. to 3 p.m. program . . . Jim Russ has become half of the traffic team at WTOP and will be covering some of the police beat as well. Dick Bertel, who works for the Voice of America, has joined WTOP as weekend midday anchor. And Faiga Levine has rejoined WTOP as a theater critic; her reports will be heard Tuesday and Thursday at 11:42 a.m. and 3:50 p.m. More Jazz

WASH-FM (97.1) has added "Jazz Up Your Sundays," one hour of jazz with Marilyn Thompson, from 6 to 7 p.m. WLTT-FM (94.7) last week introduced a Sunday morning jazz show. Tally

WETA-FM (90.9) raised $75,577 in its lastest auction, topping the last total of $50,000. Specials

WXTR-FM (104.1) is airing the 54-hour "History of Rock and Roll," hosted by Top 40 innovator Bill Drake, from 3 p.m. to midnight today and 9 a.m. to midnight Saturday, Sunday and Monday . . . WTOP plans to run hourly reports on protecting personal property and financial assets by Paul Hencke of the Research Institute of America tomorrow and Sunday at 20 minutes after each hour . . . WMAL's John Lyon and Ed Walker will emcee "Straight From the Heart," a benefit for the drug rehabilitation center Straight, at Constitution Hall at 8 p.m. tomorrow. The music will be local barbershop and Sweet Adeline groups . . . Tom Gauger of WMAL will be talking Tuesday at 2:05 to actor William Christopher, who starred in "M*A*S*H" and is currently at the Hayloft Theater in "The Seven Year Itch" . . . WETA will carry an address by Sen. Robert Dole (R-Kan.) from the National Press Club Wednesday at 1 p.m. Honors

WINX was cited by the Montgomery County Human Rights Commission for its Human Rights/Equal Opportunity Award. The station is also in the running for an award from the National Radio Broadcasters Association for its "Project Graduation," an effort by teens to help other teens have an accident-free prom and graduation season.