In typical checkerboard fashion, several stations announced personnel changes this week: Mark St. John, who has held programming jobs in Montgomery, Ala., and Asheville, N.C. takes over Monday as program director at WAVA-FM (105.1) . . . Daniel DeVany has been named producer/ announcer at WETA-FM (90.9) . . . Mary Bartone, who worked for the old WPKX-AM (730), which is now simulcasting with its new classical rock sister, WCXR-FM (105.9), has moved to WMZQ-FM (98.7) to do its weekday 7 p.m. to midnight shift . . . At the new WCXR-FM, Bob Brooks, a 20-year veteran of album-oriented rock and contemporary hit formats, has joined the staff from 3 to 7 p.m. . . . Jack Sheehan, most recently an assignment editor at a West Palm Beach, Fla., television station, is now morning news anchor at WWRC-AM (980) . . . Last Monday Dick Doty, formerly of the Washington Broadcast News, started a five-minute report, ''The Other Side of the News,'' weekdays on WNTR-AM (1050).

Q-107's Campaign

WQRX-FM (107.3) introduced a new five-minute ad campaign this week with a statuesque, attractive ''spokeswoman.'' ''She's pushing the image of the station,'' says Vivienne Vaughan, director of advertising and promotions. ''She represents anything you want her to be.'' In a reference to the last campaign of the station, which was a provocative ''life style'' piece showing a man showering and exercising in the morning, this one is not subtle but direct. The script says in part, ''Some peop;e think the TV spots Q-107 has done in the past have been a little too hot. Well, Q-107 plays the hottest music and they do have the hottest contests.''

Jazz on WLTT

Starting Sunday, WLTT-FM (94.7) will introduce ''The WLTT Jazz Brunch'' from 10 a.m. to noon with host Steve Allan. ''We have found there is growing interest on the part of our listeners in getting exposed to this kind of music, said program directors Bob Hughes. The mix will include Earl Klugh, George Benson and Al Jarreau. Last week we incorrectly reported the slogan of WLTT. As Jim Keating, general manager of WLTT, points out, ''We pay a lot of money to let people know we are Light Rock, Less Talk.''

School Series

Next week on WKYS-FM (93.9), news reporter Bob Hainey will take a look at an experimental program in eight District schools that encourages students to discuss current issues with experts. The reports on how teens are being taught to cope with drugs and career development will air at 7:50 a.m. and 3:50 p.m. Monday through Friday.

Public Starts

Tonight marks a renewal and a debut on WETA-FM (90.9). Robert Aubrey Davis starts a new season of the newly named ''Capital City Concerts'' at 8. The National Musical Arts group is featured tonight. AT 10, ''Songs for Aging Children,'' a survey of 1960s musicians hosted by Davis and Martin Goldsmith looks at the works of two shows: ''Voigt's voices.'' a call-in and interview show with Daisey Voigt every Tuesday from 9:30 to 10:30 a.m., and Bob Sidran's ''On Records,'' a jazz program on Tuesdays from 3 to 4 p.m.

Black History Specials

On weekdays in February, which is celebrated as Black History Month, WPFW is having a 30-minute quiz each day at noon. Fred fair will be asking the questions from the game BLACKFAX . . . WHUR-FM(96.3) is using another black trivia game, Rise 'n' Fly, as a basis for a quiz five times a day through February . . . WDJY-FM (100.3) has produced its own series of daily spotlights on famous blacks, called ''25 Black People Your Child Should Know.'' The 90 second spots are played 12 times a day.

Valentines and Mardi Gras

Mark on your datebook at least seven ways to say ''I Love You'' next Friday. Jackson Weaver and Frank Hardin are moving to the Washington Hilton that day and are asking guests to pay $50 for the Leukemia Society and the privelege of having Karen henderson, Bill Mayhugh, Andy Ockershausen, Tony Renaud and other WMAL-AM(630) notables serve breakfast at 7 a.m . . . . WASH-FM(97.1) is hosting the marriage of two listeners at 8 a.m. during a remote of ''The Continental Breakfast Show'' at the Ritz-Carlton Hotel . . . WBMW-FM (106.7) will have an ''almost newlywed game'' with Jon Murphy . . . Katy Daley of WMZQ-AM (1390) will read love notes from listeners from noon to 1 p.m. Jim Elliot and Scott Woodside of Q-107 also will read love notes on the air. The early morning pair are asking those who send a minimum $5 donation to Children's Hospital . . . WWRC is having a ''Sweetheart's Ball'' at 8 p.m. at the Shoreham Hotel . . . WGAY-FM (99.5) will feature Keath Barrie's ''On the Subject of Love,'' an hour of songs and poetry, at 8 p.m.