In the midst of celebrating its ninth anniversary, WPFW-FM (89.3) announced this week that it will be starting a building campaign next year and that it is developing a pilot for a daily 90-minute news magazine.

"Last year we were able to put three studios in place, and our next step . . . is getting our own building," said station manager Marita Rivero. The station is organizing a three-year campaign to get the funds.

The Pacifica Foundation outlet, which is the largest black-owned, minority-managed public station in the country, has been operating out of a building at Seventh and H streets NW for almost eight years. The improvements in the production facilities, said Rivero, would enable WPFW to "cover our local community much more." She said she hopes the pilot for the news show will be ready in May or June. WPFW is throwing a party to celebrate its anniversary Sunday from 4 to 9 p.m. at the Panorama Room, 1600 Morris Rd. SE. The tab is $15, and Rep. John Conyers (D-Mich.) is expected to be the host. A Charity Weekend

The annual leukemia radiothon hosted by Bill Mayhugh of WMAL-AM (630) kicks off at 8 a.m. Sunday from the Omni Shoreham. Mayhugh, who has raised more than $3.2 million for the Leukemia Society in the past 14 years, will be talking with Redskins Jay Schroeder and Mark Moseley, D.C. School Superintendent Floretta McKenzie and Prince George's County Executive Parris Glendening. Many others will be stopping by during the 12-hour drive . . . And today, WLTT-FM (94.7) helps sponsor the celebrity waiter luncheon for the American Lung Association of Northern Virginia at the Radisson Mark Plaza Hotel in Alexandria. The event, which begins at 11:30 a.m. and costs $35, will feature Sen. John Warner, Reps. Stan Parris and Frank Wolf, Redskins coach Joe

Gibbs and, from WLTT, Steve Allan, Bill Hamlin and Dave Arlington. Job Switch

Dave Bartlett, former news director of the old news/talk WRC, has been named director of programming at NBC'S TALKNET unit in New York. This is Bartlett's first job out of Washington, where since 1970 he has worked at the Independent Television News Association and as managing editor of Metromedia's national news bureau. "The offer was too good to refuse. TALKNET is a very lively operation and talk radio is hot with the networks and NBC is one of the main players," said Bartlett. Another Remote

Tony Renaud takes his "Sinatra and Friends Show" to Atlantic City, N.J., tomorrow, and Sinatra himself is expected to drop in. Also scheduled for the 10 p.m.-to-1 a.m. show are Buddy Greco, Red Buttons and Frankie Randall. Datebook

Tonight at 8 WETA-FM (90.9) will broadcast a celebration of Johann Sebastian Bach's 301st birthday sponsored by the Washington Bach Consort at the J.W. Marriott Hotel. Robert Aubry Davis of WETA will portray the composer, and Lyn Farmer, director of general programming for the Voice of America, will emcee while the Bach Consort performs Bach's "Greatest Hits." The event starts at 6:30 p.m. and costs $25 . . . Tom Gauger of WMAL will be the master of ceremonies tomorrow at the Opera Ball benefit, sponsored by the National Lyric Opera Company, at the Capital Hilton at 7:30 p.m. . . . Diane Rehm of WAMU-FM (88.5) will be the honorary chairwoman of the dinner and auction of the Montgomery County chapter of the American Red Cross tomorrow at 7:30 p.m. at the Crowne Plaza in Rockville . . . WWDC-AM (1260) is celebrating its third anniversary with a dance tomorrow night at the Washington Marriott Hotel, but the event is already sold out. Charity Tally

WGMS-FM/AM (103.5/570) helped raise $200,000 for the National Symphony Orchestra's annual fundraiser last weekend . . . With the help of WAVA-FM (105.1), "Rally in the Alley" raised $4,000 for Martha's Table. Special Features

Frank Harden and Jackson Weaver of WMAL are helping the U.S. Army Field Band mark its 40th year this morning with an in-studio concert . . . WINX-AM (1600) is presenting a "Buddy Holly Special" tomorrow and Sunday from 3 to 5 p.m. . . . Jamie McIntyre of WTOP-AM (1500) has researched a 10-part series, "Miles to Go," on the Metro rail system that will air Monday through Friday . . . WMAL will be playing songs that were nominated in the past for Oscars tomorrow through Monday night, when this year's Oscars will be announced. And WWRC-AM (980) will be highlight music that has won . . . On Thursday, WPFW will devote the day Thursday to poetry and jazz, with producers Bob Tyner and Grace Cavalieri assembling Washington poets to read to the sounds of America's classic music, jazz.