Before revision: In the United States, Part 15 of the U.S. Federal Communications Commission rules specifies that no license is needed if range of the transmitter does not exceed .
After revision: , although the Part 15 rules specify that the field strength should not exceed 250 µV/m (48db) at 3 meters, which is less than the service contour for commercial stations (60db), necessary for the satisfactory reception of FM stereoIn the United States, Part 15 of the U.S. Federal Communications Commission rules specifies that no license is needed if range of the transmitter does not exceed .