Washington's radio airwaves will be quieter this week. WWDC AM-FM newscaster Robin Quivers, best known as bad-boy disk jockey Howard Stern's sidekick, left WWDC Friday and starts tomorrow as a general assignment reporter at WCBM in Baltimore. Quivers was the woman behind the infectious, often raucous laughter which accompanied Stern's frequent aural outrages.

The news of Quivers' departure came as a surprise to Stern, who has worked with Quivers in an adjoining booth for two years.

"Robin and I have not been on the greatest of terms lately, so the first I heard about it was Friday afternoon--her last day," said Stern, who is leaving the station himself next month for New York's WNBC-AM.

"I think Quivers wanted to get into straight news, maybe TV eventually, so I guess she needed more news credibility," Stern said. "I think it's horrible that she's left. She's a tremendous talent."

WCBM news director Bob Shilling said Quivers "started inquiring about a position right after the WNBC thing came down." On Monday, Shilling's station switches its format from adult contemporary to news/talk. "Robin used to work in Baltimore as a life-style reporter for WFBR, so I was familiar with her work, and she's a native Baltimorean," he said. "I'll be using her in a more 'straight' sense."

Stern said he plans to use "different guest newscasters" to fill in for the month. "Today we had Arnold Schwarzenegger, we're getting Billie Jean King, other people," he said. Voices for the "guest newscasters" are supplied by Stern's versatile producer, "Earth Dog" Fred Norris.

WWDC vice president and general manager Goff Lebhar said Quivers' resignation is not connected with Stern's imminent departure for WNBC in New York. "I can't speak for Robin," Lebhar said. "She came in to tell me she didn't want to be a two-man act anymore. She came to the station as a serious newswoman, and it was difficult for her to create any serious news identity on that show. She had to leave this market to do it."

"You're dealing with a lot of talent there," Lebhar said. "We want her to stay--she's an employe you want to have on your team."

Quivers could not be reached for comment.