---
kind: "section"
citation: "47 C.F.R. § 95.1775"
title: "47"
number: "95.1775"
heading: "GMRS modulation requirements."
url: "https://uscodex.org/cfr/47/95.1775"
---

# §95.1775. GMRS modulation requirements.


Each GMRS transmitter type must be designed to satisfy the modulation requirements in this section. Operation of GMRS stations must also be in compliance with these requirements.

- (a) **Main channels.** The peak frequency deviation for emissions to be transmitted on the main channels must not exceed ± 5 kHz.
- (b) **462 MHz interstitial channels.** The peak frequency deviation for emissions to be transmitted on the 462 MHz interstitial channels must not exceed ± 5 kHz.
- (c) **467 MHz interstitial channels.** The peak frequency deviation for emissions to be transmitted on the 467 MHz interstitial channels must not exceed ± 2.5 kHz, and the highest audio frequency contributing substantially to modulation must not exceed 3.125 kHz.
- (d) **Overmodulation.** Each GMRS transmitter type, except for a mobile station transmitter type with a transmitter power output of 2.5 W or less, must automatically prevent a higher than normal audio level from causing overmodulation.
- (e) **Audio filter.** Each GMRS transmitter type must include audio frequency low pass filtering, unless it complies with the applicable paragraphs of [§ 95.1779](/cfr/47/95.1779.md) (without filtering).
  - (1) The filter must be between the modulation limiter and the modulated stage of the transmitter.
  - (2) At any frequency (f in kHz) between 3 and 20 kHz, the filter must have an attenuation of at least 60 log (f/3) dB more than the attenuation at 1 kHz. Above 20 kHz, it must have an attenuation of at least 50 dB more than the attenuation at 1 kHz.

## Notes

### Authority

Authority: 47 U.S.C. 154, 303, 307.

### Source

Source: 82 FR 41104, Aug. 29, 2017, unless otherwise noted.