This is a list of broadcast station classes applicable in much of North America under international agreements between the United States, Canada and Mexico. Effective radiated power (ERP) and height above average terrain (HAAT) are listed unless otherwise noted.

All radio and television stations within 320 kilometers (about 200 miles) of the US-Canada or US-Mexico border must get approval by both the domestic and foreign agency. These agencies are Industry Canada/Canadian Radio-television and Telecommunications Commission (CRTC) in Canada, the Federal Communications Commission (FCC) in the US, and the Federal Telecommunications Institute (IFT) in Mexico.

AM

This diagram illustrates how the AM radio spectrum is classified in North America. .mw-parser-output .legend{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .legend-color{display:inline-block;min-width:1.25em;height:1.25em;line-height:1.25;margin:1px 0;text-align:center;border:1px solid black;background-color:transparent;color:black}.mw-parser-output .legend-text{}  Clear-channel; classes A, B and D   Regional; classes B and D   Local; classes B and C
This diagram illustrates how the AM radio spectrum is classified in North America.
  Clear-channel; classes A, B and D
  Regional; classes B and D
  Local; classes B and C

Station class descriptions

All domestic (United States) AM stations are classified as A, B, C, or D. [1]

Notes:

Former system

AM station classes were previously assigned Roman numerals from I to IV in the US, with subclasses indicated by a letter suffix. Current class A is equivalent to the old class I; class B is the old classes II and III, with class D being the II-D, II-S, and III-S subclasses; and class C is the old class IV.

The following conversion table compares the old AM station classes with the new AM station classes:

Old Domestic Station Class New Domestic Station Class
I A
II B
III B
IV C
II-S D
III-S D
II-D
(Daytime Only)
D

AM station classes and clear channels listed by frequency

See also: North American Regional Broadcasting Agreement and Regional Agreement for the Medium Frequency Broadcasting Service in Region 2

The following chart lists frequencies on the broadcast company band, and which classes broadcast on these frequencies; Class A and Class B, 10,000 watt and higher (full-time) stations in North America which broadcast on clear-channel station frequencies are also shown.

By international agreement, Class A stations must be 10,000 watts and above, with a 50,000 watt maximum for the US and Canada, but no maximum for other governments in the region. Mexico, for example, typically runs 150,000 to 500,000 watts, but some stations are grandfathered at 10,000 to 20,000 watts at night; by treaty, these sub-50,000 watt Mexican stations may operate with a maximum of 100,000 watts during the daytime.[3]

Because the AM broadcast band developed before technology suitable for directional antennas, there are numerous exceptions, such as the US use of 800 (kHz) and 900 non-directionally in Alaska, limited to 5 kW at night; and 1050 and 1220, directionally, in the continental US, and without time limits; each of these being assigned to specific cities (and each of these being Mexican Class I-A clear channels). In return for these limits on US stations, Mexico accepted limits on 830 and 1030 in Mexico City, non-directionally, restricted to 5 kW at night (both of these being US Class I-A clear channels).

Channel
Type
Frequency
(kHz)
Available
Classes
Assignment
Old class designation in ()
530 In the US, reserved for low power
AM Travelers' Information Stations
Clear 540 A, B, D CBK Watrous, Saskatchewan: Class A (I-A)
CBT Grand Falls-Windsor, Newfoundland and Labrador: Class A (I-B)
XEWA San Luis Potosí, San Luis Potosí: Class A (I-A)
WFLF Pine Hills, Florida: Class B (II-B)
Regional 550 (A), B, D CMBV Wajay, Cuba: Class A "Rio" grant: 500 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 560 B, D
Regional 570 (A), B, D CMEA Santa Clara, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 580 (A), B, D CMAA Pinar del Rio, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a regional channel
KMJ Fresno, California Class B (III-A) 50 kW all hours; directional all hours
Regional 590 (A), B, D CMCA San Antonio Vegas, Cuba: Class A "Rio" grant: 150 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 600 (A), B, D CMKA San German, Cuba: Class A "Rio" grant: 150 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 610 B, D
Regional 620 (A), B, D CMDA Colon, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 630 (A), B, D CMHA Camaguey, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a regional channel
Clear 640 A, B, D KFI Los Angeles, California: Class A (I-A)
KYUK Bethel, Alaska: Class A (I-N)
CBN St. John's, Newfoundland and Labrador: Class A (I-B) NARBA grant: 10 kW non-directional all hours
Clear 650 A, B, D WSM Nashville, Tennessee: Class A (I-A)
KENI Anchorage, Alaska: Class A (I-N)
Clear 660 A, B, D WFAN New York City: Class A (I-A)
KFAR Fairbanks, Alaska: Class A (I-N)
KTNN Window Rock, Arizona: Class B (II-B)
CMDC Colon, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a US clear channel
Clear 670 A, B, D WSCR Chicago, Illinois: Class A (I-A)
KDLG Dillingham, Alaska: Class A (I-N)
KBOI Boise, Idaho: Class B (II-A)
CMBC Arroyo Arena, Cuba: Class A "Rio" grant: 50 kW all hours; special grant of a Cuban Class A on a US clear channel
Clear 680 A, B, D KNBR San Francisco, California: Class A (I-B) ND-U
KBRW Barrow, Alaska: Class A (I-N)
WRKO Boston, Massachusetts: Class B (II-B)
WCBM Baltimore, Maryland: Class B (II-B)
WPTF Raleigh, North Carolina: Class B (II-B)
Clear 690 A, B, D CKGM Montreal, Quebec: Class A (I-A)
CBU Vancouver, British Columbia: Class B (II-B)
XEWW Tijuana, Baja California: Class A (I-B) NARBA grant: 50 kW, directional all hours; currently 77 kW days, 50 kW nights, directional all hours
WOKV Jacksonville, Florida: Class B (II-B)
CMEC Santa Clara, Cuba: Class A "Rio" grant: 50 kW all hours; special grant of a Cuban Class A on a Canadian clear channel
Clear 700 A, B, D WLW Cincinnati, Ohio: Class A (I-A)
KBYR Anchorage, Alaska: Class A (I-N)
Clear 710 A, B, D WOR New York City: Class A (I-B)
KIRO Seattle, Washington: Class A (I-B)
KSPN Los Angeles, California: Class B (II-B)
WAQI Miami, Florida: Class B (II-B)
Clear 720 A, B, D WGN Chicago, Illinois: Class A (I-A)
KOTZ Kotzebue, Alaska: Class A (I-N)
KDWN Las Vegas, Nevada: Class B (II-A)
Clear 730 A, B, D CKAC Montreal, Quebec: Class A (II-B) ("Rio" grant: promotion to Class A)
XEX Mexico City: Class A (I-A)
CMHC Camaguey, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a Mexican clear channel
Clear 740 A, B, D CFZM Toronto, Ontario: Class A (I-A)
KCBS San Francisco, California: Class B (II-B) Formerly KQW San Jose, California
WYGM Orlando, Florida: Class B (II-B)
KRMG Tulsa, Oklahoma: Class B (II-B)
KTRH Houston, Texas: Class B (II-B)
CMAC Pinar del Rio, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a Canadian clear channel
Clear 750 A, B, D WSB Atlanta, Georgia: Class A (I-A)
KFQD Anchorage, Alaska: Class A (I-N)
CBGY Bonavista, Newfoundland and Labrador: Class A (I-B) (New station; Grandfathered at 10 kW)
KMMJ Grand Island, Nebraska: Class B (II-B)
KXTG Portland, Oregon: Class B (II-B)
Clear 760 A, B, D WJR Detroit, Michigan: Class A (I-A)
KGB San Diego, California: Class B (II-B)
CMKC Cacocun, Cuba: Class A "Rio" grant: 75 kW all hours; special grant of a Cuban Class A on a US clear channel
Clear 770 A, B, D WABC New York City: Class A (I-A)
KKOB Albuquerque, New Mexico: Class B (II-A)
KCHU Valdez, Alaska: Class A (I-N)
KTTH Seattle, Washington: Class B (II-B)
Clear 780 A, B, D WBBM Chicago, Illinois: Class A (I-A)
KNOM Nome, Alaska: Class A (I-N)
KKOH Reno, Nevada: Class B (II-A)
Regional 790 (A), B, D CMAC Guanabacoba, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a regional channel
Clear 800 A, B, D XEROK Ciudad Juárez, Chihuahua: Class A (I-A)
CKLW Windsor, Ontario: Class B (II-B)
CMEB Santa Clara, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a Mexican clear channel
Clear 810 A, B, D KGO San Francisco, California: Class A (I-B)
WGY Schenectady, New York: Class A (I-B) ND-U, but KGO was the originally assigned dominant station
WHB Kansas City, Missouri: Class B (II-B)
WKVM San Juan, Puerto Rico: Class B (II-B)
Clear 820 A, B, D WBAP Fort Worth, Texas: Class A (I-A)
KCBF Fairbanks, Alaska: Class A (I-N)
Clear 830 A, B, D WCCO Minneapolis, Minnesota: Class A (I-A)
KLAA Orange, California: Class B (II-B)
XEITE Mexico City, Mexico: Class B (II-B) NARBA grant: 5 kW all hours; present operation 10 kW days, 5 kW nights
Clear 840 A, B, D WHAS Louisville, Kentucky: Class A (I-A)
KXNT North Las Vegas, Nevada: Class B (II-B)
Clear 850 A, B, D KOA Denver, Colorado: Class A (I-B) ND-U
KICY Nome, Alaska: Class A (I-N)
WEEI Boston, Massachusetts: Class B (II-B)
WTAR Norfolk, Virginia: Class B (II-B)
Clear 860 A, B, D CJBC Toronto, Ontario: Class A (I-A)
KTRB San Francisco, California: Class B (II-B) Presently operating at 7.5 kW nights
CMDB Colon, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a Canadian clear channel
Clear 870 A, B, D WWL New Orleans, Louisiana: Class A (I-A)
Clear 880 A, B, D WCBS New York City: Class A (I-A)
KRVN Lexington, Nebraska: Class B (II-A)
CMAB Pinar del Rio, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a US clear channel
Clear 890 A, B, D WLS Chicago, Illinois: Class A (I-A)
KBBI Homer, Alaska: Class A (I-N)
KDXU St. George, Utah: Class B (II-A)
CMHB Camaguey, Cuba: Class A "Rio" grant: 30 kW all hours; special grant of a Cuban Class A on a US clear channel
Clear 900 A, B, D XEW Mexico City: Class A (I-A)
CKBI Prince Albert, Saskatchewan: Class A (II-B)
CMKB Cacocun, Cuba: Class A "Rio" grant: 200 kW days, 50 kW nights; special grant of a Cuban Class A on a Mexican clear channel
Regional 910 (A), B, D CMAC Guanabacoba, Cuba: Class A "Rio" grant: 75 kW all hours; special grant of a Cuban Class A on a regional channel
Regional 920 B, D
Regional 930 B, D
Clear 940 A, B, D CINW Montreal, Quebec: Class A (I-B)
XEQ Mexico City: Class A (I-B) ND-U
KFIG Fresno, California: Class B (II-B)
Regional 950 B, D KJR Seattle, Washington Class B (II-B) 50 kW all hours; directional all hours
WWJ Detroit, Michigan: Class B (II-B) 50 kW all hours; directional all hours
Regional 960 B, D
Regional 970 B, D
Regional 980 A (only CKNW), B, D CKNW New Westminster, British Columbia: Class A
Clear 990 A, B, D CBW Winnipeg, Manitoba: Class A (I-A)
CBY Corner Brook, Newfoundland and Labrador: Class A (I-B)
WTLN Orlando, Florida: Class B (II-B)
Clear 1000 A, B, D WMVP Chicago, Illinois: Class A (I-B)
KOMO Seattle, Washington: Class A (I-B)
XEOY Mexico City, Mexico: Class A (I-B) NARBA grant: 10 kW all hours; present operation 50 kW days, 10 kW nights
Clear 1010 A, B, D CBR Calgary, Alberta: Class A (I-A)
CFRB Toronto, Ontario: Class A (II-B) (Class II-B promoted to Class A)
WINS New York City: Class B (II-B)
CMBX Wajay, Cuba: Class A "Rio" grant: 500 kW all hours; special grant of a Cuban Class A on a Canadian clear channel
Clear 1020 A, B, D KDKA Pittsburgh, Pennsylvania: Class A (I-A)
KVNT Eagle River, Alaska: Class A (I-N)
KCKN Roswell, New Mexico: Class B (II-A)
KTNQ Los Angeles, California: Class B (II-B)
Clear 1030 A, B, D WBZ Boston, Massachusetts: Class A (I-A)
KTWO Casper, Wyoming: Class B (II-A)
XEQR Mexico City, Mexico: Class B (II-B) NARBA grant: 5 kW all hours; present operation 50 kW days, 5 kW nights
Clear 1040 A, B, D WHO Des Moines, Iowa: Class A (I-A)
Clear 1050 A, B, D CHUM Toronto, Ontario: Class B (II-B)
XEG Monterrey, Nuevo León: Class A (I-A)
WEPN New York City: Class B (II-B) NARBA grant: 50 kW all hours, directional all hours; present operation: same
Clear 1060 A, B, D KYW Philadelphia, Pennsylvania: Class A (I-B)
XEEP Mexico City: Class A (I-B) NARBA grant: 20 kW all hours; present operation 50 kW days, 20 kW nights
Clear 1070 A, B, D KNX Los Angeles, California: Class A (I-B) ND-U
CBA Moncton, New Brunswick: Class A (I-B) ND-U (Silent)
Clear 1080 A, B, D WTIC Hartford, Connecticut: Class A (I-B)
KRLD Dallas, Texas: Class A (I-B)
KOAN Anchorage, Alaska: Class A (I-N)
KFXX Portland, Oregon: Class B (II-B)
Clear 1090 A, B, D KAAY Little Rock, Arkansas: Class A (I-B)
WBAL Baltimore, Maryland: Class A (I-B)
XEPRS Rosarito Beach, Baja California: Class A (I-B)
KFNQ Seattle, Washington: Class B (II-B)
Clear 1100 A, B, D WTAM Cleveland, Ohio: Class A (I-A)
KNZZ Grand Junction, Colorado: Class B (II-A)
KFAX San Francisco, California: Class B (II-B)
Clear 1110 A, B, D WBT Charlotte, North Carolina: Class A (I-B)
KFAB Omaha, Nebraska: Class A (I-B)
KRDC Pasadena, California: Class B (II-B)
Clear 1120 A, B, D KMOX St. Louis, Missouri: Class A (I-A)
KPNW Eugene, Oregon: Class B (II-A)
Clear 1130 A, B, D KWKH Shreveport, Louisiana: Class A (I-B)
WBBR New York City: Class A (I-B)
CKWX Vancouver, British Columbia: Class A (I-B)
KTLK Minneapolis, Minnesota: Class B (II-B)
Clear 1140 A, B, D WRVA Richmond, Virginia: Class A (I-B)
XEMR Apodaca, Nuevo León: Class A (I-B)
KHTK Sacramento, California: Class B (II-B)
Regional 1150 B, D
Clear 1160 A, B, D KSL Salt Lake City, Utah: Class A (I-A)
WYLL Chicago, Illinois: Class B (II-B)
Clear 1170 A, B, D KFAQ Tulsa, Oklahoma: Class A (I-B)
WWVA Wheeling, West Virginia: Class A (I-B)
KJNP North Pole, Alaska: Class A (I-N)
Clear 1180 A, B, D WHAM Rochester, New York: Class A (I-A)
KOFI Kalispell, Montana: Class B (II-A)
Clear 1190 A, B, D KEX Portland, Oregon: Class A (I-B)
WOWO Fort Wayne, Indiana: Class B (I-B) Former I-B downgraded to Class B by licensee's request; 9.8 kW nights
WLIB New York City: Class B (II-B) 10 kW days, 30 kW nights
XEWK-AM Guadalajara, Jalisco, Mexico: Class A (I-B) NARBA grant: 10 kW all hours; present operation 50 kW days, 10 kW nights
Clear 1200 A, B, D WOAI San Antonio, Texas: Class A (I-A)
WMUZ Taylor, Michigan: Class B (II-B)
Clear 1210 A, B, D WPHT Philadelphia, Pennsylvania: Class A (I-A)
KGYN Guymon, Oklahoma: Class B (II-A)
Clear 1220 A, B, D XEB Mexico City: Class A (I-A)
WHKW Cleveland, Ohio: Class B (II-B) NARBA grant: 50 kW all hours, directional all hours; present operation: same
Regional 1230 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1230 C Stations in conterminous 48 states
Regional 1240 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1240 C Stations in conterminous 48 states
Regional 1250 B, D
Regional 1260 B, D CFRN Edmonton, Alberta: Class A (III-B) Class III-B promoted to Class A, but operating on a Class III frequency
Regional 1270 B, D
Regional 1280 B, D
Regional 1290 B, D
Regional 1300 B, D
Regional 1310 B, D
Regional 1320 B, D
Regional 1330 B, D
Regional 1340 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1340 C Stations in conterminous 48 states
Regional 1350 B, D
Regional 1360 B, D
Regional 1370 B, D
Regional 1380 B, D KRKO Everett, Washington Class B (III-A) 50 kW all hours; directional nights
Regional 1390 B, D
Regional 1400 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1400 C Stations in conterminous 48 states
Regional 1410 B, D
Regional 1420 B, D
Regional 1430 B, D
Regional 1440 B, D
Regional 1450 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1450 C Stations in conterminous 48 states
Regional 1460 B, D
Regional 1470 B, D
Regional 1480 B, D
Regional 1490 B Stations in Alaska, Hawaii, Puerto Rico, and the United States Virgin Islands
Local 1490 C Stations in conterminous 48 states
Clear 1500 A, B, D WFED Washington, D.C.: Class A (I-B)
KSTP Saint Paul, Minnesota: Class A (I-B)
Clear 1510 A, B, D WLAC Nashville, Tennessee: Class A (I-B)
WMEX Boston, Massachusetts: Class B (II-B) downgraded to 10 kW days, 100 watts nights, non-directional at all times
KGA Spokane, Washington: Class B (I-B) Former I-B downgraded to Class B by licensee's request; 15 kW nights
Clear 1520 A, B, D WWKB Buffalo, New York: Class A (I-B)
KOKC Oklahoma City, Oklahoma: Class A (I-B)
KQRR Oregon City, Oregon: Class B (II-B)
KKXA Snohomish, Washington Class B (II-B) 50 kW all hours; directional all hours
Clear 1530 A, B, D KFBK Sacramento, California: Class A (I-B)
WCKY Cincinnati, Ohio: Class A (I-B)
Clear 1540 A, B, D KXEL Waterloo, Iowa: Class A (I-B)
ZNS-1 Nassau, Bahamas: Class A (I-A)
KMPC Los Angeles, California: Class B (II-B)
Clear 1550 A, B, D XERUV Xalapa, Veracruz: Class A (I-B) NARBA grant: 10 kW non-directional
CBEF Windsor, Ontario: Class A (I-B) NARBA grant: 10 kW directional all hours
KKOV Vancouver, Washington: Class B (II-B)
Clear 1560 A, B, D KNZR Bakersfield, California: Class A (I-B) Only US Class A grandfathered at 10 kW nights, increased daytime power to 25 kW
WFME New York City: Class A (I-B)
Clear 1570 A, B, D XERF Ciudad Acuña, Coahuila: Class A (I-A) NARBA grant: 250 kW, now operating at 100 kW
Clear 1580 A, B, D CKDO Oshawa, Ontario: Class A (I-A) operating at 10 kW
KBLA Santa Monica, California: Class B (II-B)
Regional 1590 B, D
Regional 1600 B, D
Regional (Expanded) 1610 In the US, used solely by low power
AM Travelers' Information Stations.
Regional (Expanded) 1620 B
Regional (Expanded) 1630 B
Regional (Expanded) 1640 B
Regional (Expanded) 1650 B
Regional (Expanded) 1660 B
Regional (Expanded) 1670 B
Regional (Expanded) 1680 B
Regional (Expanded) 1690 B
Regional (Expanded) 1700 B

FM

[4]

Station class description

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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) 300 m to 600 m 91.8 km
C0 100 kW 300 m to 450 m 83.4 km
C1 up to 100 kW under 300 m 72.3 km
C2 up to 50 kW up to 150 m 52.2 km
C3 up to 25 kW up to 100 m 39.1 km
C4 (US rulemaking) up to 12 kW up to 100 m 33.3 km
B up to 50 kW up to 150 m 65.1 km
B1 up to 25 kW up to 100 m 44.7 km
A 100 W to 6 kW (3 kW in Mexico) up to 100 m 28.3 km (24 km in Mexico)
AA (Mexico)[5] up to 6 kW (the former limit for A) up to 100 m 28 km
D up to 250 W ERP except US non-translators to 10W TPO
up to 50 W (Mexico)
unlimited
up to 45 m (Mexico)
unspecified
5 km (Mexico)
L1 (US, also LP100) 50 W to 100 W up to 30 m 5.6 km
L2 (US, also LP10) 1 W to 10 W up to 30 m 3.2 km
LP (Canada) 10-50 W
VLP (Canada) up to 10 W
unlicensed signal strength of 250 µV/m (US), 100 µV/m (Canada) unspecified measured at 3 m (US), 30 m (Canada)

Notes:

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:[6]

FM station
class
Reference
(maximum)
facilities for
station class
(ERP / HAAT)
FM
protected
or primary
service
contour
Distance to
protected or
primary
service
contour
Distance to 70
dBu city-grade
or principal
community
coverage
contour
Class A 6 kW
100 m (328 ft)
60 dBu (1.0mV/m) 28.3 km (17.6 mi) 16.2 km (10.1 mi)
Class B1 25 kW
100 m (328 ft)
57 dBu (0.7mV/m) 44.7 km (27.8 mi) 23.2 km (14.4 mi)
Class B 50 kW
150 m (492 ft)
54 dBu (0.5mV/m) 65.1 km (40.5 mi) 32.6 km (20.3 mi)
Class C3 25 kW
100 m (328 ft)
60 dBu (1.0mV/m) 39.1 km (24.3 mi) 23.2 km (14.4 mi)
Class C2 50 kW
150 m (492 ft)
60 dBu (1.0mV/m) 52.2 km (32.4 mi) 32.6 km (20.3 mi)
Class C1 100 kW
299 m (981 ft)
60 dBu (1.0mV/m) 72.3 km (44.9 mi) 50.0 km (31.1 mi)
Class C0 100 kW
450 m (1,476 ft)
60 dBu (1.0mV/m) 83.4 km (51.8 mi) 59.0 km (36.7 mi)
Class C 100 kW
600 m (1,969 ft)
60 dBu (1.0mV/m) 91.8 km (57.0 mi) 67.7 km (42.1 mi)

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 300 feet above average terrain.

FM zones

FM broadcast zones in the US
FM broadcast zones in the US

The US is divided into three zones for FM broadcasting: I, I-A and II. The zone where a station is located may limit the choices of broadcast class available to a given FM station.

Zone I in the US includes all of Connecticut, the District of Columbia, Delaware, Illinois, Indiana, Massachusetts, Maryland, New Jersey, Ohio, Pennsylvania, Rhode Island, and West Virginia. It also includes the areas south of latitude 43.5°N in Michigan, New Hampshire, New York, and Vermont; as well as coastal Maine, southeastern Wisconsin, and northern and eastern Virginia.

Zone I-A includes California south of 40°N, as well as Puerto Rico and the US Virgin Islands.

Zone II includes the remainder of the continental US, plus Alaska and Hawaii.

In Zones I and I-A, there are no Class C, C0, or C1 stations. However, there are a few Class B stations with grandfathered power limits in excess of 50 KW, such as WETA (licensed for Washington DC in zone I, at a power of 75 kW ERP), WNCI (Columbus, Ohio in zone I, at 175 kW ERP), KPFK (Los Angeles in zone I-A, at 110 KW ERP), and the most extreme example being WBCT (Grand Rapids, Michigan, in zone I, at 320  kW ERP).

TV

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This list is incomplete; you can help by adding missing items. (August 2008)

Full-power stations in the US

Notes:

All full-power analog television station transmissions in the US were terminated at midnight Eastern Daylight Time on June 12, 2009.[7][8] Many broadcasters replaced their analog signal with their digital ATSC signal on the same transmission channel at that time.

Full-power stations in Canada

Notes:

Low-power TV (US)

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LPTV (secondary) (suffix: -LP, or a sequential-numbered callsign in format W##XX with no suffix for analog or with -D suffix for digital, or -LD for low-power digital stations):

The LPTV (low-power television) service was created in 1982 by the FCC to allocate channels for smaller, local stations, and community channels, such as public access stations. LPTV stations that meet additional requirements such as children's "E/I" core programming and Emergency Alert System broadcasting capabilities can qualify for a Class A (-CA) license.[12]

Broadcast translators, boosters, and other LPTV stations are considered secondary to full-power stations, unless they have upgraded to class A. Class A is still considered LPTV with respect to stations in Canada and Mexico.

Class A television (US)

Main article: Class A television service

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Class-A stations (US) (suffix: -CA or -CD for digital class A):

The class-A television class is a variant of LPTV created in 2000 by the FCC to allocate and protect some low-power affiliates. Class-A stations are still low-power, but are protected from RF interference and from having to change channel should a full-service station request that channel.[13]

Additionally, class-A stations, LPTV stations, and translators are the only stations currently authorized to broadcast both analog and digital signals, unlike full-power stations which must broadcast a digital signal only.

Low-power TV (Canada)

In Canada, there is no formal transmission power below which, a television transmitter is considered broadcasting at low power. Industry Canada considers that a low power digital television undertaking "shall not normally extend a distance of 20 km in any direction from the antenna site," based on the determined noise-limited bounding contour.[14]

Mexico

All digital television stations in Mexico have -TDT callsign suffixes. Analog stations, which existed until December 31, 2016, had -TV callsign suffixes.

The equivalent of low power or translator service in Mexico is the equipo complementario de zona de sombra, which is intended only to fill in gaps between a station's expected and actual service area caused by terrain; a station of this type shares the callsign of another station. In analog, these services often were broadcast on the same or adjacent channels to their parent station, except in certain areas with tight packing of television stations (such as central Mexico). In digital, these services usually operate on the same RF channel as their parent station, except for those with conflicting full-power applications (XHBS-TDT Cd. Obregón, Son., channel 30 instead of 25), in certain other cases where it is technically not feasible (XHAW-TDT Guadalupe, NL, channel 26 instead of 25) or to make way for eventual repacking on upper UHF (XHPNW-TDT has four shadows on 33, its post-repacking channel, instead of 39).

Equipos complementarios can relay their parent station, or a station that carries 75% or more of the same programming as its parent station.[15]

Stations of either type may have unusually low or high effective radiated powers. XHSMI-TDT in Oaxaca is licensed for two watts in digital. The highest-powered shadows are XEQ-TDT Toluca and XHBS-TDT Ciudad Obregón, both at 200 kW.

FCC service table

The United States Federal Communications Commission lists the following services on their website for television broadcasting:

Broadcast class Service Suffixes used or call sign examples
Television allotment (analog) TA An allocation of a frequency to a city of license for which no corresponding call sign or license has been assigned. FCC placeholder for possible future construction permits or frequencies allocated to non-US broadcast use. No call sign, identifier is a date (yymmdd) followed by a sequential two-letter value in the US FCC database.
Full-service TV (analog) TV -TV or none (such as "WABC-TV" and "WMYD") Since the shutdown of all full power analog stations in June 2009, used only for historical records.
Class A (analog) CA -CA, or a translator-style call sign (such as "KTFB-CA")
Low-power station (analog) or translator LP -LP, or a translator-style call sign (such as "KDMD-LP" and "K13IO" with the 2 digits denoting the channel of operation)
TV boosters TB Rare. These use the parent station's call sign plus a sequential number, such as WSTE1, WSTE2, WSTE3. Nameplates for on-channel repeaters bear the parent station's call sign, followed by "booster".[16] See distributed transmission. If the station is digital, and has on-channel boosters, they would typically be named WSTE-DT1, WSTE-DT2, WSTE-DT3 and so on.
TV auxiliary (analog backup) service TS no specific suffix (uses same call sign as main transmitter)
NTSC (analog) petition for a channel change NN no specific suffix; uses same call sign as the station which made a request for a number/channel change (for NTSC/analog stations, and low-power repeaters, such as those registered as TX).
Digital Television
(full power)
DT -DT, -TV or none (such as KGLA-DT, WSKY-TV or KOHD). Some stations formerly used -HD, but this has become obsolete (though it may sometimes still be seen identifying the station's main subchannel in a PSIP listing). The -DT suffix, optional for digital-only stations, was used primarily to distinguish a DTV transmission from an analog signal of the same broadcast (or is seen identifying the main subchannel of a station on a PSIP display); likewise, -TV is optional except if the eponymous radio stations exist. A similar suffix -DTV, is used on all television stations in Japan.
Digital Class-A CD -CD(such as "WDNI-CD" and "WYYW-CD") Some stations briefly used -DC as well (this has since become obsolete). A scant few still use translator-style call signs with the -D suffix (such as "K36ID-D").
Digital Low-power LD -LD or translator-style calls with -D suffix (such as "WBND-LD" and "W25AA-D"), occasionally no suffix (uses same call sign as main transmitter). Some stations briefly used -DL as well (this has since become obsolete). Some full-powered stations (such as WOIO, WXMI and WLS-TV) have been granted approval for fill-in translators within their broadcast market to better cover outlying towns or heavily urbanied areas, particularly by stations with a VHF digital signal. These are technically -LD stations, but have the same call-sign as their parent station (such as WLS-TV or WOIO, and not as WLS-LD or WOIO-LD, though they could be considered as such for ease of differentiating the low-power repeater from its parent), similar to a Distributed Transmission System (but on different frequencies).
Digital special temporary authority (STA) DS no specific suffix; uses same call sign as station making a request for permission from the FCC to use a channel, power level or transmitter location not permanently allocated for one particular station. Temporary assignments retain, unmodified, the call sign of the corresponding permanent allocation; this includes translator-style calls (a format, such as W55ZZ-D, based on RF channel number plus a sequential identifier) even on those temporarily moving to another frequency.
Digital Television distributed transmission system (multiple transmitter sites) DD no specific suffix (uses same call sign as main transmitter); this is usually requested for a single-frequency network and to tailor coverage area to the needs of the viewers in the station's service area (such as covering towns and farmland, and not mountainous terrain or the ocean)
Digital auxiliary (backup) service DX
(not to be confused with DXing)
no specific suffix (uses same call sign as main transmitter)
Digital rulemaking petition DR no specific suffix; uses same call sign as station making this request to add or modify a digital channel allocation
Land mobile use of a TV channel (TV RF channels 14-20 only) LM As "LM" is used in the FCC database to indicate reallocation of an entire channel, but not to identify individual users transmitting in that spectrum, a 6 MHz LM allocation does not itself carry a TV-style call sign. The spectrum of TV channels 14-20 is called "T-band" in LMR use.[17] Repeaters that operate in such an allocation use a 3 MHz offset instead of 5 MHz as normally used in the 450-470 MHz range.
ATSC 3.0 Futurecast Experimental Broadcasts EX Used for officially licensed experimental 4K/2160p Ultra HDTV broadcast stations, such as WRAL-TV's UHDTV simulcast, WRAL-EX.

See also

References

  1. ^ "AM Station Classes, and Clear, Regional, and Local Channels". fcc.gov. Federal Communications Commission. 11 December 2015. Retrieved July 5, 2019.
  2. ^ "Industry Canada Broadcasting Database". Archived from the original on 2013-12-07. Retrieved 2011-01-29.
  3. ^ "Clear Channel Stations". www.oldradio.com.
  4. ^ "FM Broadcast Station Classes and Service Contours". fcc.gov. 11 December 2015.
  5. ^ IFT: Disposición Técnica IFT-002-2016 "Especificaciones y requerimientos para la instalación y operación de las estaciones de radiodifusión 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.
  6. ^ "FM Broadcast Station Classes and Service Contours". FCC. Federal Communications Commission. 11 December 2015. Archived from the original on 1 March 2016. Retrieved 28 October 2018. See Talk page.
  7. ^ A New Era in Television Broadcasting Archived 2007-11-23 at the Wayback Machine - DTVTransition.org
  8. ^ "Congress delays DTV switch". Christian Science Monitor. 4 February 2009.
  9. ^ [1] - FCC DA-09-1253
  10. ^ [2] Searching for the -DT suffix returns only 91 stations; -TV returns 903, searching for TV stations with no suffix at all returns 1,827. Searches conducted 29 Jan 2011.
  11. ^ [3] - FCC regulation 73.1560(c)(2)
  12. ^ "Low Power Television (LPTV) Service". fcc.gov. 17 May 2011.
  13. ^ [4]
  14. ^ "Part 10: Application and Procedures and Rules for Digital Television (DTV) Undertakings" (PDF). ic.gc.ca.
  15. ^ IFT: Disposición Técnica IFT-013-2016 "Especificaciones y requerimientos mínimos para la instalación y operación de estaciones de televisión, equipos auxiliares y equipos complementarios", which became effective on January 1, 2017, provides the guidelines for the operation of digital television stations and their shadows.
  16. ^ "US CFR 47 Part 74G - 74.733 UHF translator signal boosters". gpoaccess.gov. Archived from the original on 2012-03-05. Retrieved 2008-07-13.
  17. ^ "TV Query Results -- Video Division (FCC) USA". www.fcc.gov.