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Low-power broadcasting

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Low-power broadcasting is the concept of broadcasting at very low power and low cost, to a small community area. These stations tend to serve small towns, or communities within large cities in the United States. There are close to 3,000 LPTV stations in the US and they are in all markets including New York City (5 stations) to Junction City, KS (2 stations). The terms "low-power broadcasting" and "micropower broadcasting" (more commonly "microbroadcasting") should not be used interchangeably, because the markets are not the same. The former term is more often used to describe stations who have applied for and received official licences. The relationship between broadcasting power and signal range is a function of many things, such as the frequency band it uses e.g, SW or FM, the topography of the country in which it operates (lots of mountains or flat), atmospheric conditions, and finally the amount of radio frequency energy it transmits. As a general rule, the more energy it transmits, the further the signal goes. LPFM, LPAM, and LPTV are in various levels of use across the world, varying widely based on the laws and their enforcement.

1 United States
2 United Kingdom
3 New Zealand
4 See also
5 External links

United States

FM radio

In the U.S., the FCC partially re-legalized LPFM licenses, after the NAB, CPB, and NPR convinced them to stop issuing the FM class D license in 1978. The new LPFM licenses in the United States may only be issued to nonprofit educational organizations and state and local governments. Also, the one and so far only "window" for applications closed in 2003, and at present, the FCC is not entertaining any new broadcast license applications, instead conducting auctions of frequencies for full power uses only.

LPFM classes in the United States

Class L1 (LP100) is from 50 to 100 watts effective radiated power (ERP).
Class L2 (L10) is at least 1 and up to 10 watts ERP.
Class D is 10 watts TPO or less, regardless of ERP, and are no longer issued for LPFM services (since 1978).

Officially, class D is still assigned to broadcast translators, though the rules are actually much looser (up to 250 watts ERP) than for true LPFM stations, though they may not broadcast their own programming. This is due to the influence of NPR and religious broadcasting companies, which often rely on translators. Since true class D stations can bump translators, they therefore have less competition in getting or keeping their own translators on the air with new class D stations kept off the air. New classes L1 and L2 are still considered class D for international purposes, but are considered to be equal in status to translators, and subordinate to full class D stations still operating. Part 15 rules are quite strict for FM, making it nearly impossible to operate a legally-unlicensed station that can be heard more than a few yards away. The rule is a signal strength of 250 µV/m at 3 meters from the antenna, set forth in 47 CFR §15.239. Radiating cable antenna systems do allow for longer, if still narrow, radiated fields and are commonly used for building broadcast systems (stadiums, dormitories, apartments, etc... with high success. Such systems are also used for specialized audiences for hearing assistance and language translation at events.

Political issues around LPFM

Many of the proponents of the new LPFM classes have been critical of the actual service. Their complaints include:

The majority of the licenses have been issued to religious broadcasters who tend to have little locally-produced programming and syndicate broadcasts originating elsewhere. Religious broadcasters counter that few secular groups are equipped to fund the continuing operations of an LPFM station.
Of the religious broadcasters, a large number have been issued to local branches of Calvary Chapel.
In some states, the local Department of Transportation operates large networks of LPFM stations that act as Highway advisory radio stations—a service traditionally operated at the fringes of the AM band—restricting the number of available channels. (reader note - these systems can be licensed to the entire AM band, but the LPFM service provides considerably greater coverage at 100w than the 10w limit on AM - hence the considerable appeal for government agencies).

The Prometheus Radio Project is a group of former microbroadcasters and current media activists formed to provide technical, legal, and organizational support to community groups wishing to start a LPFM station. They have presented testimony before Congress and the FCC which advocates for community-owned LPFM stations, not conglomerate-owned. Major Conglomerates have created a nation with common, national playlists and only promote certain artists or programs. Groups such as Prometheus Radio Project display their concerns with the loss of diversity on the radio. Issues Concerning the Radio Broadcasting Preservation Act of 2000:

Due to legal requirements in the controversial Radio Broadcasting Preservation Act of 2000, LPFM stations must be separated by at least 0.6 MHz from all other stations (even though most experts claim 0.4 MHz would be sufficient), in most large metropolitan areas there are no available frequencies for LPFM stations at all.
Low Power FM will result in increased "crosstalk" interference. The FCC reports that interference comes across only as noise or hissing and not overlapping voices.
Major investors in radio believe LPFM services prevent the development of digital radio. The FCC denies such claims.

Local Community Radio Act of 2007

The Local Community Radio Act of 2007 was recently approved by the Senate Commerce Committee. This bill aims to increase the number of low power FM stations that will be broadcast. The bill was introduced to the committee seven years ago in a fight to open up the radio stations to thousands of low power stations. It would also help to make licensing restrictions more lenient to the non-commercial stations. The stations given licenses would possibly give different view points from the commercial radio stations.

Policies to help LPFM

The Telecommunications Act of 1996 was implemented in order to foster competition between the firms in the Telecommunications Sector including those stations of LPFM. Reed Hundt, the FCC chair at the time, said that the FCC imposed the act to ought to encourage “diversity in programming and diversity in the viewpoints expressed on this powerful medium that so shapes our culture.” The act “mandates interconnection of telecommunications networks, unbundling, non-discrimination, and cost-based pricing of leased parts of the network.” However the act relies upon the behaviors of companies to do what is in their best interest and does not enforce punishment towards firms that do not abide by the act. Furthermore research suggests that the Act has led to “less competition, fewer viewpoints, and less diversity in programming.”

AM radio

LPAM is generally not licensed in the U.S., but is allowed on the campus of any school, so long as the normal Part 15 rules are adhered to when measured at the edge of the campus. Many currently licensed college radio stations started out this way. Stations may have freestanding radio antennas, or may use carrier current methods to ride on power lines. These signals cannot pass through transformers, however, and are prone to the electromagnetic interference of the alternating current. Stations may also use 'leaky' or radiating cable transmission systems. Tens of thousands of these stations have been in operation around the country since the 1940s, and many continue to thrive where conventional licensing is unavailable and the operators still desire to conform to Federal laws. The exception is Travelers' Information Stations (TIS), sometimes also called highway advisory radio (HAR). These are licensed LPAM stations set up by local transport departments to provide bulletins to motorists and other travelers regarding traffic and other delays. These are often near highways and airports, and occasionally other tourism attractions such as national parks. Only governments may have licenses for TIS/HAR stations, and music is disallowed. These operate under FCC Part 90.242 and may be licensed by quasi-governmental agencies as well (many are used by chemical and nuclear facilities for emergency evacuation information systems) as well as by public safety entities for mobile operations.

Television

LPTV (-LP) is common in the U.S., Canada and most of the Americas where most stations originate their own programming. Stations that do not originate their own programming are designated as translators (-TX). LPTV stations that meet additional requirements such as Children's "E/I" core programming and Emergency Alert System can qualify for a Class A (-CA) license. Unlike FM and AM, unlicensed use of TV bands is prohibited for broadcasting. The amateur television channels do allow for some very limited non-entertainment transmissions however, with some repeaters airing NASA TV during Space Shuttle missions when they are not in local use.

United Kingdom

Temporary low-power stations are allowed at times via a Restricted Service Licence. Since 2001 longterm LPFM licences have been available in remote areas of the country. These are currently used for many establishments including military bases, universities and hospitals with fixed boundaries.

New Zealand

In New Zealand residents are allowed to broadcast licence free at 0.5 watts EIRP in the FM guardbands from 88.1 to 88.7 (or 88.1 to 88.4 within 120 km of the Sky Tower in Auckland) and from 106.7 to 107.7 MHz under a General User Radio License (GURL) issued by Radio Spectrum Management. Broadcasters on these frequencies are required to cease operations if they interfere with other, licensed broadcasters and have no protection from interference from other licensed or unlicensed broadcasters. There exists a 25 km rule: You may operate two transmitters anywhere (close together), but a third transmitter must be 25 km away. There are efforts on self-regulation of the broadcasters themselves.