After several years of declining ratings, WRQX-FM (107.3) has dropped its 11-year-old Top 40 format and its "Q107" logo in favor of an up-tempo, adult contemporary music format. In the switch, made Friday at noon, the WRQX call letters remain, but the station now is being described on the air as "Mix 107.3 -- not too hard, not too light."

"It is current {hit} intensive with a greater depth in oldies," said WRQX President and General Manager Maureen Lesourd of the new format, known in the industry as "Hot AC." The switch followed more than a year of intensive research and a series of focus groups underwritten by the station's owners, Capital Cities/ABC, Lesourd said.

"We will concentrate on popular music from the '90s with selected songs from the '70s and '80s. They are hits -- very well-tested songs," said Lesourd. "The format is tailored to what the research shows listeners want to hear. It's right smack in the middle of the ACs (WLTT-FM, 94.7, and WASH-FM, 97.1) and the CHRs (contemporary hit radio or Top 40 -- WAVA-FM, 105.1)," said Lesourd, adding that the station's target audience will continue to be 25-to-34-year-olds. She said that while Q107's music attracted the target audience, its teenage image "was holding us back."

The format change comes after at least two years of persistent rumors that the station was planning to go in another director because of poor ratings.

David Lawrence, host of the ratings-troubled morning program for the past 18 months, was let go. Lawrence, 31, said Friday that weeks ago he had heard through the grapevine that he was to be replaced and that he had no hard feelings. In fact, Lawrence made a previously scheduled personal appearance Saturday at Pearl Vision in Wheaton Plaza with management's approval. Lawrence, who married a Riggs Bank executive less than two months ago, said he intends to stay in Washington. Program director Lorrin Palagi said Friday that Jack Diamond, formerly of country-format KSON in San Diego, Calif., was scheduled to make his debut as host of the morning program this morning. Diamond, 36, who grew up in Silver Spring, worked a night shift at Rockville's WINX-AM (1600) during his junior year at then-Robert E. Peary High School. In his two years of hosting the morning drive show at KSON, the station went from No. 7 to No. 1 in the 25-to-54-year-old market, according to Diamond.

"I do a friendly, off-the-wall, David Letterman sort of show. Nothing nasty, just fun stunts," he said.

Veteran afternoon announcer Gary Spears was also let go, and was replaced by the station's production director, Loo Katz. Katz has worked at the station since early 1989 when he was fired from his midday slot at Top 40 competitor WAVA. By late Friday afternoon, Spears was discussing his future with WAVA General Manager Alan Goodman. Today Spears will be meeting with programmers at Chicago's WBBM-FM. Lesourd attributed Lawrence's and Spears's departures to the need for change: "Those shifts are so important and we needed a different sound." All other staffers at WRQX will keep their shifts and music director Laura Shostak will continue selecting the station's music, Lesourd said.

In the coming weeks, the station will spend more than $500,000 advertising the format change on local television stations. "We'll have extremely good saturation," Lesourd said.

Reached at the station just after the noon announcement, morning news anchor Barbara Britt said, "I think it's great. It's exciting. I think everybody was ready, everybody is happy. This has been coming for a long time. It's very positive." Britt said she believed the new programming was now aimed at "the Washington woman." No Changes at WDJY-FM

"Bee J' " Johnson, program director and morning host of WDJY-FM (100.3), said Friday that no changes are on tap for the station. For months rumors have circulated that WDJY was in the midst of a format change; coincidentally the most mentioned format has been Hot AC, but Johnson said, "We are onto something here. We are sort of a "New AC" -- jazzy rhythm-and-blues leaning more to the R&B side than the lighter side." Listeners have been told the station is playing the "best mix of music," but Johnson said the station is discontinuing that description because WRQX is now touting its "mix." (This could be a problem for WRQX since it shares a large listening area, and is close on the dial to Baltimore's similarly programmed WWMX-FM (106.5) or "Mix 106").

WDJY's Johnson figured the change was good for WRQX: "It was a smart thing for them to do, because they were going to be waxed by WAVA." However, Johnson does not believe the WRQX change is going to hurt WDJY. "In fact, it may help us some" because WRQX will probably offer lighter music, he said, while WDJY will offer varying degrees of jazz cuts -- from pop/jazz artists such as Anita Baker, Luther Vandross and Regina Belle, to crossover stars Paul Jackson Jr., Dwight Sills, Oleta Adams and Michael Franks, to straight-ahead artists such as Chick Corea. Says Johnson, "We are closer to doing the right thing than we ever have been."

Of the rumors, Johnson, a 25-year veteran radio announcer who signs off each morning with "If you can't run with the big dogs, stay on the porch," says he ignores them.

"The rumors are just that until they come true."