47 CFR 78.111: Frequency tolerance.

Stations in this service shall maintain the carrier frequency of each authorized transmitter to within the following percentage of the assigned frequency.

Frequency band (MHz) Frequency tolerance

Fixed (percent) Mobile (percent)

1,990 to 2,110 0.005

6,425 to 6,525 0.005

6,875 to 7,125 0.005

12,700 to 13,250 1 0.005 0.005

17,700 to 18,820 0.003

18,820 to 18,920 0.001

18,920 to 19,700 0.003

1 Stations that employing vestigal sideband AM transmissions shall maintain their operating frequency within 0.0005% the visual carrier, and the aural carrier shall be 4.5 MHz ±1 kHz above the visual carrier frequency.