List of North American broadcast station classes Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! ===Station class description=== {{Confusing section|date=October 2010}} {| class="wikitable" |- !Class !Effective Radiated Power (ERP, calculated using transmitter power and antenna HAAT) !Antenna Height Above Average Terrain (HAAT) !Reference distance |- |'''C''' |100 kW (or higher for grandfathered stations) |{{convert|300|to|600|m|ft|0|abbr=on}} |{{convert|91.8|km|mi|1|abbr=on}} |- |'''C0''' |100 kW |{{convert|300|to|450|m|ft|0|abbr=on}} |{{convert|83.4|km|mi|1|abbr=on}} |- |'''C1''' |up to 100 kW |under {{convert|300|m|ft|0|abbr=on}} |{{convert|83.4|km|mi|1|abbr=on}} |- |'''C2''' |up to 50 kW |up to {{convert|150|m|ft|0|abbr=on}} |{{convert|52.2|km|mi|1|abbr=on}} |- |'''C3''' |up to 25 kW |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|39.1|km|mi|1|abbr=on}} |- |''C4 (US rulemaking)'' |up to 12 kW |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|33.3|km|mi|1|abbr=on}} |- |'''B''' |up to 50 kW |up to {{convert|150|m|ft|0|abbr=on}} |{{convert|65.1|km|mi|1|abbr=on}} |- |'''B1''' |up to 25 kW |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|44.7|km|mi|1|abbr=on}} |- |'''A''' |100 W to 6 kW (3 kW in Mexico) |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|28.3|km|mi|1|abbr=on}} ({{convert|24|km|mi|0|abbr=on}} in Mexico) |- |'''A1''' (Canada)[https://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf01153.html] |50 W to 250 W |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|18|km|mi|0|abbr=on}} |- |'''AA''' (Mexico)<ref>[http://www.ift.org.mx/sites/default/files/dofpift170316102_1.pdf IFT: Disposici贸n T茅cnica IFT-002-2016 "Especificaciones y requerimientos para la instalaci贸n y operaci贸n de las estaciones de radiodifusi贸n sonora en frecuencia modulada en la banda de 88 a 108 MHz"] is the current document that defines FM station classes and operating parameters in Mexico.</ref> |up to 6 kW (the former limit for A) |up to {{convert|100|m|ft|0|abbr=on}} |{{convert|28|km|mi|0|abbr=on}} |- |'''D''' |up to 250 W ERP except US non-[[broadcast translator|translators]] to 10W [[transmitter power output|TPO]]<br />up to 50 W (Mexico) |unlimited<br />up to {{convert|45|m|ft|0|abbr=on}} (Mexico) |unspecified<br />{{convert|5|km|mi|0|abbr=on}} (Mexico) |- |'''L1''' (US, also '''LP100''') |50 W to 100 W |up to {{convert|30|m|ft|0|abbr=on}} |{{convert|5.6|km|mi|1|abbr=on}} |- |'''L2''' (US, also '''LP10''') |1 W to 10 W |up to {{convert|30|m|ft|0|abbr=on}} |{{convert|3.2|km|mi|1|abbr=on}} |- |'''LP''' (Canada) |10-50 W | | |- |'''VLP''' (Canada) |up to 10 W | | |- |''unlicensed'' |[[signal strength]] of 250 碌V/m (US), 100 碌V/m (Canada) |unspecified |measured at {{convert|3|m|ft|0|abbr=on}} (US), {{convert|30|m|ft|0|abbr=on}} (Canada) |} '''Notes:''' * Canada protects all radio stations out to a [[signal strength]] of 0.5[[mV/m]] (54dBu), whereas only commercial B stations in the US are. Commercial B1 in the US is 0.7mV/m (57dBu), and all other stations are 1.0mV/m (60dBu). [[Reserved band|Noncommercial-band]] stations (88.1 to 91.9) are not afforded this protection, and are treated as C3 and C2 even when they are B1 or B. C3 and C2 may also be reported internationally as B1 and B, respectively. * Class C0 is for former C stations, demoted at request of another station which needs the downgrade to accommodate its own facilities. * In practice, many stations are above the maximum HAAT for a particular class, and correspondingly must downgrade their power to remain below the reference distance. Conversely, they may ''not'' increase power if they are ''below'' maximum HAAT. * All class D (including L1 and L2 [[LPFM]] and translator) stations are secondary in the US, and can be bumped or forced off-air completely, even if they are not just a repeater and are the only station a licensee has. * The United States is divided into regions that have different restrictions for FM stations. Zone I (much of the [[US Northeast]] and [[Midwest]]) and I-A (most of [[California]], plus [[Puerto Rico]]) is limited to classes B and B1, while Zone II (everything else) has only the C classes. All areas have the same classes for A and D. * Power and height restrictions were put in place in 1962. A number of previously existing stations were [[grandfather clause|grandfathered]] in, such as [[KRUZ (FM)|KRUZ]] in [[Santa Barbara, California]], and [[WLFP (FM)|WLFP]] in [[Memphis, Tennessee]]. The following table lists the various classes of FM stations, the reference facilities for each station class, and the protected and city grade contours for each station class:<ref>{{cite web |title=FM Broadcast Station Classes and Service Contours |url=https://www.fcc.gov/media/radio/fm-station-classes |url-status=dead |archive-url=https://web.archive.org/web/20160301145227/https://www.fcc.gov/media/radio/fm-station-classes |archive-date=1 March 2016 |website=FCC |publisher=Federal Communications Commission |access-date=28 October 2018 |date=11 December 2015}} See [[Talk:List of North American broadcast station classes#FM Broadcast Station Classes and Service Contours|Talk page]].</ref> {| class="wikitable" |- ! FM station<br />class ! Reference<br />(maximum)<br />facilities for <br />station class<br />([[Effective radiated power|ERP]] / [[Height above average terrain|HAAT]]) ! FM<br />protected<br />or primary<br />service<br />contour ! Distance to<br />protected or<br />primary<br />service<br />contour ! Distance to 70<br />dBu city-grade<br />or principal<br />community<br />coverage<br />contour |- | Class A | 6 kW<br />{{convert|100|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|28.3|km|mi|1|abbr=on}} | {{convert|16.2|km|mi|1|abbr=on}} |- | Class B1 | 25 kW<br />{{convert|100|m|ft|0|abbr=on}} | 57 dBu (0.7mV/m) | {{convert|44.7|km|mi|1|abbr=on}} | {{convert|23.2|km|mi|1|abbr=on}} |- | Class B | 50 kW<br />{{convert|150|m|ft|0|abbr=on}} | 54 dBu (0.5mV/m) | {{convert|65.1|km|mi|1|abbr=on}} | {{convert|32.6|km|mi|1|abbr=on}} |- | Class C3 | 25 kW<br />{{convert|100|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|39.1|km|mi|1|abbr=on}} | {{convert|23.2|km|mi|1|abbr=on}} |- | Class C2 | 50 kW<br />{{convert|150|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|52.2|km|mi|1|abbr=on}} | {{convert|32.6|km|mi|1|abbr=on}} |- | Class C1 | 100 kW<br />{{convert|299|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|72.3|km|mi|1|abbr=on}} | {{convert|50.0|km|mi|1|abbr=on}} |- | Class C0 | 100 kW<br />{{convert|450|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|83.4|km|mi|1|abbr=on}} | {{convert|59.0|km|mi|1|abbr=on}} |- | Class C | 100 kW<br />{{convert|600|m|ft|0|abbr=on}} | 60 dBu (1.0mV/m) | {{convert|91.8|km|mi|1|abbr=on}} | {{convert|67.7|km|mi|1|abbr=on}} |} Historically, there were local "Class A" frequencies (like AM radio's class C stations) to which only class A stations would be allocated & the other frequencies could not have a class A. According to the 1982 FCC rules & regulations, those frequencies were: 92.1, 92.7, 93.5, 94.3, 95.3, 95.9, 96.7, 97.7, 98.3, 99.3, 100.1, 100.9, 101.7, 102.3, 103.1, 103.9, 104.9, 105.5, 106.3 & 107.1. Stations on those twenty frequencies were limited to having equivalent signals no greater that 3KW at {{convert|300|ft|m|0|abbr=off|sp=us}} above average terrain. Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page