Unlicensed Radio Frequencies: A Guide

Introduction

Not all radio frequencies require a license to use, making communication easier for individuals, families, and businesses. These unlicensed frequencies are regulated for public use by the FCC (Federal Communications Commission) in the U.S., and they offer accessible communication options without the complexities of licensing.

Below is a detailed list of popular unlicensed radio frequencies and their common uses.

List of Unlicensed Radio Frequencies

Family Radio Service (FRS)

  • Frequency Range: 462-467 MHz (UHF)
  • Power Limit: 0.5 to 2 watts
  • Use Case: Short-range communication via walkie-talkies for families, hiking, camping, and local coordination. No license is required, but the range is limited to a few miles in open areas

Multi-Use Radio Service (MURS)

  • Frequency Range: 151-154 MHz (VHF)
  • Power Limit: 2 watts
  • Use Case: Suitable for small businesses and personal communication. MURS allows external antennas, increasing range. These frequencies are often used for driveway alarms, handheld radios, and farm communications

Citizen Band (CB) Radio

  • Frequency Range: 26.965-27.405 MHz (11-meter band)
  • Power Limit: 4 watts AM, 12 watts SSB
  • Use Case: Primarily used by truckers and hobbyists for long-range communication. CB radio allows “skip” transmissions, meaning signals can bounce off the atmosphere to reach hundreds of miles under certain conditions

Industrial, Scientific, and Medical (ISM) Band

  • Frequency Range: 902-928 MHz, 2.4-2.5 GHz, 5.725-5.875 GHz
  • Use Case: Typically used for Wi-Fi, Bluetooth, and RFID communication. Devices operating on these bands, such as routers and smart home gadgets, do not require individual licenses

Wireless Microphones and Intercoms

  • Frequency Range: 49 MHz and 902-928 MHz
  • Use Case: Wireless microphones, baby monitors, and intercom systems commonly use these frequencies without the need for licensing.

Summary

Unlicensed radio frequencies offer a convenient way to communicate without needing a license, but each service comes with limitations on range, power, and interference.

For applications like FRS for family outings, MURS for small business operations, or CB radio for long-haul communication, these options provide accessible solutions for a variety of needs.

The ISM bands are used by Wi-Fi and Bluetooth but also provide an alternative for wireless experimentation (considering transmission rules).