47 C.F.R. § 78.111
Frequency tolerance.
Cite as 47 C.F.R. § 78.111 (2026)
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.
[52 FR 7145, Mar. 9, 1987, as amended at 68 FR 12776, Mar. 17, 2003]