Eddie Gallaher, WASH-FM's veteran morning man, has joined WWDC-AM, spearheading a format change at WWDC-AM.

Goff Lebhar, vice president and general manager of WWDC-AM and FM said the new format, effective yesterday, will be middle of the road music, "aimed at people 35 to 54 years of age . . . Sinatra, Streisand, Carpenters, some big band, but not exclusively." Lebhar said the format has been changed at the AM station, which previously carrying the album-rock programming of WWDC-FM, because of a lack of interest on the part of younger listeners, who won't go to AM stations for music that is available in stereo rock formats on FM radios. Lebhar said listeners in older age brackets are known to tune in to AM stations for their needs.

"We're out to get numbers," said Gallaher, who has spent the last 14 years of his 38-year Washington radio career as morning announcer at WASH. Gallaher's last day on WASH is tomorrow; he hopes to begin his new show on St. Patrick's Day. "I'll be playing what I call 'unforgettable music,' all the great songs. It's different because you can understand the lyrics. No sexual references here, no songs about cocaine."

Gallaher and Lebhar refused to discuss contract terms, but Gallaher said "the things WWDC offered me were so attractive that I couldn't turn them down. It's a question of my personal security and a need for a change." Lebhar said Gallaher has signed a long-term contract.

WASH-FM's new morning man is its new program director, Bill Tanner, who comes from Miami's number one station, WHYI-FM, where he was vice president of programming since 1979 and had his own successful daily show, "Tanner in the Morning." John Bodnar returns to afternoon drive, and Bob Duckman takes the midday show (10 a.m.-3 p.m.).

"DATELINE" DATA: National Public Radio has successfully launched "NPR Dateline," a daily public affairs program, hosted by Sanford Ungar, former cohost of NPR's "All Things Considered." Executive producer Jeff Rosenberg said the show has been designed for in-depth, single-subject coverage, like a news magazine cover story. "In fact, we originally wanted to call it 'Cover Story,' " Rosenberg said of the program, which has been devoted to subjects such as the "decline of Broadway," the pope as politician and five mayors' views on the problems of the cities. NPR Dateline airs weekdays on WETA-FM (90.9) at 4:30 p.m. and on WAMU-FM (88.5) the next morning at 5:30.

SALE OF THE SYMPHONY . . . WGMS (570 AM, 103.5 FM) will kick off its "radiothon" to benefit the National Symphony Orchestra with a live broadcast of an NSO concert, conducted by Mstislav Rostropovich, with guest pianist Andre Watts, at 7 o'clock tomorrow night. Items to be auctioned on the air include a lunch with Art Buchwald and an excursion on the Goodyear blimp. Call 469-7777 for information about the radiothon, which continues through Sunday, or to make pledges.

CURRENTS . . . News/talk station WRC-AM (980) is involved in an effort to raise $500,000 to provide 3,000 bulletproof vests for D.C. patrol officers. A spokesman for WRC said about $56,000 was raised during its last radiothon. Listeners are asked to mail contributions to MPDC Vest Fund, Box 6191, Washington, D.C. 20044 . . . NPR's new audio adaptation of George Lucas' movie "The Empire Strikes Back" can be heard on WAMU-FM at 7:30 p.m. Sundays and on WETA-FM at 12:30 p.m. Saturdays.