Howard Stern, surrounded by strippers and cheered by thousands of fans, began promoting his switch to satellite radio yesterday at a rally where he handed out free boom boxes and satellite subscriptions.

“Down with the FCC!” the shock jock told a legion of sign-waving backers. “They have ruined commercial broadcasting.” The fans agreed, screaming “Howard rules!” as their hero addressed the overflow crowd. Stern supporters spilled into the streets surrounding Union Square, stopping noontime traffic throughout the neighborhood.

“Most people think it, but don’t say it,” said Stern fan Peter Frankel, the 50-year-old president of a suburban janitorial company, as he walked off with a free Sirius boom box. “Howard Stern says it. It’s healthy for society.”

Across the square on Fifth Avenue, the culture war took on another slant, with fans of the rival satellite radio XM staging their own rally, hoisting placards touting the shock jock antics of its “Opie & Anthony” radio team.

Mr. Stern will be able to say anything he wants once he starts at Sirius Satellite Radio, which is free of Federal Communications Commission restrictions. Stern has battled for years with the FCC over the content of his salacious show.

Last month, Mr. Stern announced he was leaving traditional radio for Sirius – even though his current syndicated show is scheduled to run through December 2005.