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Your car radio may be revealing your tastes

A device made by an Alabama company can tell what station your car radio is tuned to. Advertisers love it, but privacy advocates fear it.

Like easy listening? Classic rock? Howard Stern? Next time you drive to a concert arena or down a freeway, your car radio could be transmitting some information of its own: your listening tastes.

For the past four years, Mobiltrak, a company in Birmingham, Ala., has been marketing a device that finds out what radio stations people are listening to inside their cars. Mobiltrak's clients include concert arenas, shopping malls and car dealerships that pay to install the shoebox-size devices at the entrances of their parking lots.

The monitor picks up signals from a car radio's oscillator, the part of the radio that tunes into the station. The data is recorded and sent via modem to Mobiltrak, which then sends an e-mail report to its clients on a daily or weekly basis.

Companies use Mobiltrak's device to determine whether the money they spend on radio advertising is being spent in the right place. Knowing the stations customers listen to as they drive in is one way of finding this out, they say.

"If we're going to spend advertising dollars in Boston to encourage people to come see Aerosmith, we want to determine which radio stations have the best opportunity of reaching an Aerosmith listener," said Mike Ferrel, president and chief executive of SFX Entertainment, a major concert promoter and venue owner and operator.

He said SFX had paid Mobiltrak "a number in the high five figures" for a three-year deal.

Another Mobiltrak user, Lenny Sage, vice president of the Universal City Nissan car dealership in Los Angeles, said, "We recognize that people channel surf, but with the amount of sources we get on a weekly basis, about 3,000 to 4,000, we think we're getting a good picture of what they listen to."

Other Mobiltrak clients include radio stations, which have commissioned the company to install monitors along major freeways and other heavily trafficked roads. "We've wired the entire market in Los Angeles, Phoenix and Atlanta," said Lucius Stone, vice president for sales and marketing at Mobiltrak.

Mobiltrak ( is not the first to monitor people's radio choices. The British Broadcasting Corp.'s television licensing group, for example, deploys vans to drive down residential streets and detect oscillator signals from televisions inside homes. The group then verifies with its database that each homeowner has a license for the television set, which is required in Britain.

Mobiltrak works without the cars' occupants being aware that their listening habits are being monitored. That has raised concerns among some privacy experts.

"The practice is deplorable, but like so many other laws relating to privacy, there are all sorts of loopholes in wiretap laws," said David Banisar, a lawyer with Privacy International, a watchdog group in London that focuses on surveillance by government and corporations.

Mobiltrak and its clients maintain that the monitoring device performs a random sweep of car radios, but does not identify the car or its occupants, and therefore does not infringe on people's privacy. "It's not personal, it's generic," Ferrel said. "We get information that a car is listening to 97.5, not that the person is listening to 97.5."

A random sampling of radio station "hits" might be considered relatively harmless, and not much different from an Internet site's recording the number of hits it gets. But couple the monitoring device with a digital camera that reads license plates, critics say, and these companies will be able to match car owners to their favorite radio stations.

"There's the opportunity and the economic motivation to match the license to the listening data," said Jason Catlett, president of Junkbusters Corp., a consumer privacy Web site ( "This would be of enormous interest to radio stations, which are paid by advertisers according to their audience demographics. Imagine if they could prove that more than 50 percent of their audience makes over $75,000 a year."

Others worry that the information could be used in the wrong way. "This opens an enormous can of worms where the commercial pressure will be to refine who is listening to what station at what time and in what place," said Joel Reidenberg, a professor of law at Fordham University.