List of North American broadcast station classes
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 (199 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.
A
NARBA
B
AM expanded band
C
grandfathered
D
Field strength
TIS/HAR — / highway advisory radio stations — Up to 10 W transmitter output power. Stations within US national parks are licensed by NTIA and not the FCC.
travelers' information stations
Unlicensed broadcasting — (see ) — 100 mW DC input to final amplifier with a 3-meter (10-foot) maximum length radiator, no license needed, may be measured at edge of campus for school stations and neighborhood broadcasters.
low-power broadcasting
Canada protects all radio stations out to a of 0.5mV/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). 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.
signal strength
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 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.
LPFM
The United States is divided into regions that have different restrictions for FM stations. Zone I (much of the 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.
US Northeast
Power and height restrictions were put in place in 1962. A number of previously existing stations were in, such as KRUZ in Santa Barbara, California, and WLFP in Memphis, Tennessee.
grandfathered
VHF low (2-6): 100 kW video analog at 1,000 feet (305 meters) in Zone I and 2,000 feet (610 meters) in Zone II and Zone III above average terrain; 10 kW in Zone I and 45 kW in Zone II and Zone III digital at 1,000 feet (305 meters) above average terrain
VHF high (7-13): 316 kW video analog at 1,000 feet (305 meters) in Zone I and 2,000 feet (610 meters) in Zone II and Zone III above average terrain; 30 kW in Zone I and 160 kW in Zone II and Zone III digital at 1,000 feet (305 meters) above average terrain
UHF (14-36): 5 MW (5,000 kW) video analog at 2,000 feet (610 meters) above average terrain; 1 MW (1,000 kW) digital at 2,000 feet (610 meters) above average terrain
- How call signs and classes are used in North America
Call signs in North America
- How callsigns and classes are used worldwide