Low power broadcasting

Low-power broadcasting refers to a broadcast station operating at a low electrical power to a smaller service area than "full power" stations within the same region, but often distinguished from "micropower broadcasting" (more commonly "microbroadcasting") and broadcast translators. LPFM, LPAM and LPTV are in various levels of use across the world, varying widely based on the laws and their enforcement.

Radio communications in Canada are regulated by the Radio Communications and Broadcasting Regulatory Branch, a branch of Industry Canada, in conjunction with the Canadian Radio-television and Telecommunications Commission (CRTC). Interested parties must apply for both a certificate from Industry Canada and a license from CRTC in order to operate a radio station. Industry Canada manages the technicalities of spectrum space and technological requirements whereas content regulation is conducted more so by CRTC.

LPFM is broken up into two classes in Canada, Low (50 watts) and Very Low (10 watts). The transmitters therefore range from 1 to 50 watts, as opposed to 1 to 100 watts in the U.S. As of 2000, 500 licenses (very low and low-power FM) have been issued. These transmitters are generally only allowed in remote areas.

Stations in the low-power class are subject to the same CRTC licensing requirements, and will generally follow the same call sign format, as full-power stations. Stations in the very low-power class formerly had to have CRTC licenses as well, although a series of CRTC regulation changes in the early 2000s exempted most such stations from licensing; a station in this class will usually not have a conventional call sign, but will instead be identified in a naming format consisting of a four-digit number preceded by the letters CH for a television station or VF for a radio station.

The regulation of spectrum space is strict in Canada, as well having restrictions on second and third adjacent channels, along with other protections for AM and FM commercial radio. In addition, because there have been a few cases that found that FM frequencies have caused interference to the aeronautical navigation and communications (NAV/COM) spectrum (though evidence is not very concrete presently), pirate radio regulation has remained very strict as well. However, the two regulating bodies do have certain exemptions. For example, low-power announcement transmitters that meet the requirement of Broadcasting Equipment Technical Standards 1, Limited Duration Special Events Distribution Undertakings, Temporary Resource Development Distribution Undertakings, and Public Emergency Radio Undertakings are a few instances, which according to certain criteria, may be exempt from certificate/license requirements.

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