47 CFR § 78.111 - Frequency tolerance.
---
identifier: "/us/cfr/t47/s78.111"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "47 CFR § 78.111 - Frequency tolerance."
title_number: 47
title_name: "Telecommunication"
section_number: "78.111"
section_name: "Frequency tolerance."
chapter_name: "FEDERAL COMMUNICATIONS COMMISSION"
subchapter_number: "C"
subchapter_name: "BROADCAST RADIO SERVICES"
part_number: "78"
part_name: "CABLE TELEVISION RELAY SERVICE"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "47 U.S.C. 152, 153, 154, 301, 303, 307, 308, 309."
regulatory_source: "37 FR 3292, Feb. 12, 1972, unless otherwise noted."
cfr_part: "78"
---
# 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.
| | | |
| --- | --- | --- |
| 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 | 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 | |
| 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]