But the antenna has had to go separately, in somebody's truck, and the truck has had trouble finding a parking space. By the time the antenna finally arrives, you can hear the rumble of the approaching marchers' drums. Hurriedly, Provizer sets it up -- a skinny rectangle of copper tubing, about as tall as a person, its base resting in a wooden toolbox on the roof of the car, padded by an old green blanket and surrounded by signs saying DON'T TOUCH FOR FEAR OF ELECTRICAL SHOCK, with a lightning bolt drawn for emphasis. Loose barbell weights and twine guy lines anchor and brace it, and a cable running through the rear passenger-side window connects it to the station's transmitter, a gray, flanged metal box the size of a patio brick. A battery, a mixing board, and other components are strewn around the seats and foot wells; the tall, angular Provizer is still clambering around connecting things as the marchers round the corner, pass by the car, and break the lock on the boarded-up building.

From this, you might conclude that Radio Free Allston, 106.1 FM, is a bit of a disorganized effort, a one-man fringe activity. But the episode with the antenna -- and pirate radio's general reputation for recklessness -- notwithstanding, Radio Free Allston is neither careless nor disorderly. In the four months since Provizer, a writer and a former producer for TV and radio, decided to venture into illegal broadcasting, he's rounded up 200 supporters, built his own transmission equipment, and won support from local civic groups and the Allston-Brighton business community.

The station is part of a larger low-power pirate-radio movement, which is challenging the way access to the public airwaves is controlled. Led by California's Free Radio Berkeley (which guided Radio Free Allston through its birth), the stations are challenging the FCC's authority on the grounds that its policies effectively restrict free speech. In an age when some analysts are touting the technology-intensive Internet as a forum for the democratic exchange of ideas, Provizer wants to deliver information on the cheap. "At this point, as far as I'm concerned, the most democratic medium is still the radio," he says. "Just about everybody has a radio."

So what he's doing, he says, is creating a community station, "a structure that affirms the most positive aspects of personal growth and community interchange," as he put it in a December flier announcing his intentions. To include as much of Allston as possible, he says, he has had the circulars translated into Spanish, Portuguese, and Vietnamese, and he hopes to get them done in Serbian as well. His volunteers include people who refer to the area as Allston-Brighton, and those who say Brighton-Allston.

Though the 20-watt station is operating in violation of federal licensing and station-power laws, it is not at all furtive about it. Its formal, official (if that word can be used) debut is scheduled for this Saturday, March 1, in a noon-to-9 p.m. marathon broadcast from Herrell's Renaissance Café, in Allston. There will be live music, a roundtable discussion among civic leaders, an original radio play, and "special surprises," Provizer says. The public is invited to attend and to participate; the show will go on under the auspices of Herrell's live-entertainment license. "Without that, I would probably be violating the law," says Mark Cooper, the owner of Herrell's and a vice-president of the Allston Board of Trade. "There's city laws and federal laws. City laws are the ones you have to worry about."

Still, the federal laws are worth considering: according to the FCC, any FM station with a broadcast range of more than 30 meters must have a license to operate. The fine for unlicensed operation can be as much as $10,000 a day (to a maximum of $75,000), and the FCC also threatens operators with criminal prosecution. "Don't do it!" conclude the guidelines on the FCC's website.

But Provizer, like others around the country, is taking the illegal route, because, he says, of another FCC rule, which requires FM stations to have a minimum power of 100 watts and AM stations 250 watts. That requirement, instituted in 1978, helped drive small, community-oriented stations out of business, in favor of larger stations with broader audiences.

And now, with the recent slackening of restrictions on how many stations one company can own in a single market, radio is becoming still less independent, with big-business stations favoring mass-market syndicated programming over locally generated shows. According to Garrett Wollman, a radio enthusiast who helps compile and maintain a website called the Boston Radio Archive, about half of Boston-area stations are now part of larger chains.

Between the power requirement and licensing fees, Provizer says, it takes hundreds of thousands of dollars -- if not millions -- to start a legal radio station. "If I could do this without doing it illegally, I would," he says.

Wollman agrees with Provizer that the 100-watt rule was a "bad and mean-spirited idea," but says he disapproves of the unlicensed broadcasters' approach. Even though station-ownership fees may be prohibitive, there are many AM stations that lease airtime, and there are still high-school or college FM stations that will allow outsiders to use some of their hours. Provizer's chosen frequency of 106.1 falls in a rare gap on the Boston radio dial, Wollman says, but it will still keep hobbyists who listen to distant stations from hearing WCOD in Hyannis, whose signal reaches here "almost all the time in the summer."

Part of the purpose of the unlicensed broadcasting is to draw attention to the state of radio regulation and ownership. Provizer, Wollman says, "is probably doing more by getting press about what he's doing than by actually broadcasting."

The people who have signed on to take part in Radio Free Allston, however, seem more interested in the station's programming than in its symbolic overtones. Music director Seth Albaum, a senior at Emerson, says he sees the station as a less professionally oriented outlet than Emerson's WERS, where he used to work. Under his guidance, the station will feature early American folk music, punk, and local music. His own show, "Space Age," will feature "a mix of sound collages, once I get around to putting them together."

Others seem to see the station as a way to get Allston life on the air. Lorraine Bossi, a retiree with no prior radio experience who's moderating the roundtable discussion, hopes to have an outlet for discussing issues on which the locals feel their opinions aren't being heard -- particularly on plans for a new Stop & Shop and on community resistance to the potential arrival of a halfway house for alcoholics. And Joy Campbell, who's working on the radio play, says it's set in a fictitious Allston group home, full of "typical people you find in Allston" (working title: The Real World: Allston).

Among Campbell's collaborators, she says, is someone who lives across the street from her, whom she'd never met before. The radio work, she says, "makes me feel like I'm starting to get to know my neighbors."

Neighborly goodwill probably won't make much of an impression on the FCC. Provizer says he hopes to establish a consistent daily broadcast time for the station, so people can reliably hear it. But what people can locate, the feds can too. "He's probably going to get stepped on pretty quickly," Wollman says, "especially if he sticks to a regular schedule."

Stations can get caught, Provizer points out, without getting shut down; Free Radio Berkeley, for one, is in the midst of a court battle with the FCC, in which it has so far staved off an injunction to stop broadcasting.

And, Provizer says, there's another way to stay ahead of the regulators: "Part of the goal of this organization is to go to other communities," he says, and to "seed the area with other stations of this type."