47 CFR § 95.2165
LPRS frequency accuracy
February 16, 2021
Each LPRS transmitter type must be designed to satisfy the frequency accuracy requirements in this section.
(a) LPRS transmitters operating on standard band (25 kHz) or extra band (50 kHz) channels must be designed such that the carrier frequencies remain within ±50 ppm of the channel center frequencies specified in §95.2163(a) and (b), respectively, during normal operating conditions.
(b) LPRS transmitters operating on narrowband (5 kHz) channels must be designed such that the carrier frequencies remain within ±1.5 ppm of the channel center frequencies specified in §95.2163(c) during normal operating conditions.