Howard Stern is using a new medium, satellite radio, to speak to the American public, but he’s using a time-tested symbol, the raised fist, to convey his “revolutionary” agenda.

Mr. Stern created the concept behind what the men and women at Sirius Satellite Radio call the “defiant fist.” An advertising agency, Euro RSCG, designed it. The logo shows a black fist with the ring and middle fingers forming an “H” for “Howard” against a gritty red background.

“It’s really simple. It’s a symbol of being a revolutionary and being a pioneer in radio,” a Sirius spokesman, Patrick Reilly, said. “He was a pioneer in terrestrial radio, and his show clearly proved that, and now he’s a pioneer and even a revolutionary in satellite radio.”

When asked if Mr. Stern intended to allude to any specific period in American history with which the fist symbol is associated – most notably the black power movement of the 1960s – Mr. Reilly said, “Howard would never be so ponderous,” before explaining that, to Mr. Stern, the fist is a “universal symbol.”

Mr. Stern isn’t the only New Yorker to adopt the fist symbol of late. Andrew Rasiej, who ran against Public Advocate Betsy Gotbaum last year on a platform of wiring New York, hung posters around the city that showed a blue fist grasping a red lighting bolt.

The signs read, “Connecting New York City: Rasiej for Public Advocate.”

Mr. Rasiej said some constituents asked whether the fist had a Soviet connotation. He said it does not.

“The fist in the air was actually a symbol from the Tennessee Valley Authority. It meant electricity for all,” Mr. Rasiej explained, referring to the New Deal program of the 1930s. “I think it was an incredibly powerful symbol that basically indicated power to people, to individuals and as a metaphor it described visually of the Internet being available everywhere, through the air.”

While the individuals adopting fists as logos seem clear on their personal reasons for using clenched hands to represent themselves, their intentions may be perceived as confusing – or even dishonorable – to outside observers.

A City Council member, Charles Barron, who is a former Black Panther, accused Mr. Stern of misappropriating the black power salute. “I think this guy needs more therapy than he needs a radio station, and he has no scruples, no principles,” he added. “He’ll do anything to get attention.”

Mr. Barron called Mr. Rasiej’s explanation of his campaign logo “bogus.”

“Using a symbol like that is electoral exploitation in his attempt to appeal to the black community,” he said. “In New York City, we’ve become the new majority along with Latinos and Asians.”

The assistant director of fact-finding at the Anti-Defamation League, Oren Segal, said a fist could convey divergent messages – from the black power salute made famous by two African-American sprinters, Tommie Smith and John Carlos, during the medal ceremony at the 1968 Olympics to its modern usage as the racist symbol of some neo-Nazi groups and the radical symbol of a Jewish extremist group, the Jewish Defense League. The fist is also used by the New York City bicycling group, Critical Mass.

“The fist is going to be popular because it conveys a certain amount of strength and militancy,” he said. “It’s almost a call to arms.”

The director of the Stanford Humanities Lab, Jeffrey Schnapp, who is the curator of a traveling exhibition, Revolutionary Tides: The Art of the Political Poster 1914-1989, said the fist is so universal a symbol that “It really transcends any specific political ideology.”

He said the image of the human fist has been used since ancient times to denote “defiance” and “willfulness” both in an offensive and a defensive sense. He said the fist with the lightning bolt could represent a harnessing of divine power.

According to Mr. Schnapp, raised fists have been used throughout history by such diverse historical groups as the French resistance, the Iranian revolution, and the Polish solidarity movement.

“It’s an extraordinary, synthetic, compact way to express a complex attitude, and most symbols have that power, that extraordinary power to compress within them a whole universe of meaning,” he said. “It’s a gesture that has become a sort of universal currency that everyone recognizes. That universality and economy makes it almost inescapable.”

To a graphic design artist, Barry Berger, the president of Barry David Berger & Associates and a professor of communications design at Pratt Institute, the “universality” of the fist removes much of its power and significance.

“I think because it is so universal and also so overused, it is not clear what individual message the sender means,” he said.

He said Mr. Barron’s response was “reasonable” for an American who lived through the social turmoil of the 1960s, but someone from a different culture or country might have an entirely different reaction. In any case, he said, both Mr. Stern and Mr. Rasiej failed to convey an individualized and clear message with their symbols.

“The whole idea of a logo is to create a unique, recognizable visual shorthand for something,” he said. “If you use a common symbol like a hand, you must use it in such a unique manner that it’s understood, or else it would be subject to confusion.”