Fred Lass, director of engineering at WRGB in Schenectady, N.Y. has posed an interesting question. Can low-power FM transmitters being used with iPods or after market XM-Radio receivers legally transmit on 87.9 MHz? He noticed articles recommending the use of 87.5, 87.7 or 87.9 MHz to avoid interference from (and to) FM radio stations. Channel 6 TV stations, with an 87.75 MHz audio subcarrier, also fall in this part of the spectrum. Car radios and nearby home receivers can receive these mini-transmitters.