home stereo: Satellite shows are interfering with some FM stations
By Clea Simon, Globe Correspondent | May 18, 2006
The majority of listeners who hear Howard Stern on Sirius Satellite Radio pay for the privilege. But a growing number who pick up shows from both XM and Sirius satellite services are getting Stern but would prefer not to. The occurrence of satellite ''bleed through" -- when regular FM programming is broken into by a satellite signal -- is small, but as the number of satellite subscribers increases, so does this radio interference problem.
Sign up for: Globe Headlines e-mail | Breaking News Alerts This interference is neither a Stern prank nor promotion. It's an unintentional side effect of the services' cost-saving measures. Satellite radio requires special receivers to pick up its signal, and when these receivers are professionally installed, they do just that. However, to attract listeners who want a low-cost option, both XM and Sirius have licensed ''do it yourself" plug-in receivers that can be used in a car or with a home stereo. These plug-in receivers, known as FM modulators, usually contain small, low-power wireless transmitters.
Once they pick up the satellite signal, the FM modulators use these low-power transmitters to rebroadcast the satellite signal to the car or home stereo on a low-end FM frequency, such as 88.1 or 88.3. This makes it possible for the user to ''tune in" satellite on their regular radio. Unfortunately, as the number of these FM modulators grows, more and more outside radios pick up their signals as well. This low-power retransmitting is allowed by the FCC's so-called Part 15 rules and isn't supposed to interfere with licensed broadcasters. But according to both listeners and traditional broadcasters, the interference is there and growing.
''We have gotten numerous complaints," says William Kuhlman, chief engineer of MIT station WMBR-FM (88.1). Listeners trying to tune in to this small MIT-based station, he says, ''hear bits of Howard Stern bleeding through into our morning shows when they commute to work." The problem is national. The Vermont public radio system in particular is encountering difficulties with its new classical radio network, according to Scott Fybush, editor of the Rochester, N.Y.-based NorthEast Radio Watch. The network is carried by repeater stations across the state. But since the network uses the 88.1 frequency, at times the repeaters rebroadcast satellite shows, instead of the public radio content.
''It's a perfect storm of circumstances," says Fybush. ''Nobody anticipated when the Part 15 rules came about that there would be so many of these devices." Another problem, he says, is that many of these low-cost receivers are manufactured overseas where, without domestic oversight, they may not all be made to the legal specifications. ''Some engineers think they are putting out more [power] than Part 15 allows," says Fybush.
The FCC is looking into the problem and is investigating both XM and Sirius. One solution, suggests Kuhlman, would be to push the satellite signals further down the dial below most stations -- to 87.9 FM for example. But this may be too little, too late.
''The cat is very much out of the bag," says Fybush. ''All of these devices are out there. There are millions in cars and homes. You can't just turn around and say none of these are legal anymore."
© Copyright 2006 Globe Newspaper Company.
The majority of listeners who hear Howard Stern on Sirius Satellite Radio pay for the privilege. But a growing number who pick up shows from both XM and Sirius satellite services are getting Stern but would prefer not to. The occurrence of satellite ''bleed through" -- when regular FM programming is broken into by a satellite signal -- is small, but as the number of satellite subscribers increases, so does this radio interference problem.
Sign up for: Globe Headlines e-mail | Breaking News Alerts This interference is neither a Stern prank nor promotion. It's an unintentional side effect of the services' cost-saving measures. Satellite radio requires special receivers to pick up its signal, and when these receivers are professionally installed, they do just that. However, to attract listeners who want a low-cost option, both XM and Sirius have licensed ''do it yourself" plug-in receivers that can be used in a car or with a home stereo. These plug-in receivers, known as FM modulators, usually contain small, low-power wireless transmitters.
Once they pick up the satellite signal, the FM modulators use these low-power transmitters to rebroadcast the satellite signal to the car or home stereo on a low-end FM frequency, such as 88.1 or 88.3. This makes it possible for the user to ''tune in" satellite on their regular radio. Unfortunately, as the number of these FM modulators grows, more and more outside radios pick up their signals as well. This low-power retransmitting is allowed by the FCC's so-called Part 15 rules and isn't supposed to interfere with licensed broadcasters. But according to both listeners and traditional broadcasters, the interference is there and growing.
''We have gotten numerous complaints," says William Kuhlman, chief engineer of MIT station WMBR-FM (88.1). Listeners trying to tune in to this small MIT-based station, he says, ''hear bits of Howard Stern bleeding through into our morning shows when they commute to work." The problem is national. The Vermont public radio system in particular is encountering difficulties with its new classical radio network, according to Scott Fybush, editor of the Rochester, N.Y.-based NorthEast Radio Watch. The network is carried by repeater stations across the state. But since the network uses the 88.1 frequency, at times the repeaters rebroadcast satellite shows, instead of the public radio content.
''It's a perfect storm of circumstances," says Fybush. ''Nobody anticipated when the Part 15 rules came about that there would be so many of these devices." Another problem, he says, is that many of these low-cost receivers are manufactured overseas where, without domestic oversight, they may not all be made to the legal specifications. ''Some engineers think they are putting out more [power] than Part 15 allows," says Fybush.
The FCC is looking into the problem and is investigating both XM and Sirius. One solution, suggests Kuhlman, would be to push the satellite signals further down the dial below most stations -- to 87.9 FM for example. But this may be too little, too late.
''The cat is very much out of the bag," says Fybush. ''All of these devices are out there. There are millions in cars and homes. You can't just turn around and say none of these are legal anymore."
© Copyright 2006 Globe Newspaper Company.
