89.1 FM is WFDU, a local college radio station out of Teaneck, NJ. I can usually hear this in southern Rockland County, NY and all the way across the Tappan Zee Bridge into White Plains. Reception depends on the weather. On Monday and Wednesdays, the station features Blues music in the mornings.
This morning, the station kept on fading out and was replaced by a James Taylor concert. I figured out that it was an iPod FM transmitter in a neighboring car. When my lane moved, I got my Blues station back. When I stopped and the lane to my left moved, I would lose the station to Sweet Baby James.
This is the first time this has happened to me on 89.1, but I notice it frequently when I listen to the venerable Newark Jazz station WBGO 88.3. FM transmitters usually are configurable for stations in the low or high end of the band. The cheap ones blanket the low frequencies and it is not unusual for me to be listening to some cool Jazz and have a rap song take over until a beat up old Nissan passes me.
I have an FM transmitter that I bought for $10 at a computer show. I will set it up with an MP3 Player so that it blasts Muddy Waters to everyone on the TZ bridge and get my revenge.