Contents

   Introduction
   Classes for U.S. AM Broadcast Stations
   Clear, Regional, and Local Channels; Steps to Follow to Determine the Domestic Class
   The Region 2 Class
   Old to New Class Conversions

Introduction

There are two fields in the CDBS database and the AM Query search results that involve the class of station. They are:

 
  • The Domestic Class (or class of the station with respect to other U.S. stations), which is generally the class of station defined in Section 73.21
     
  • The Region 2 Class, which is generally the class of station as defined in the Region 2 [Western Hemisphere] AM Agreement. This class also corresponds to the class in the 1984 U.S.-Canadian AM Agreement and the 1986 U.S.-Mexican Agreement.

Classes for U.S. AM Broadcast Stations

In MM Docket 87-267, the Commission reclassified all domestic [United States] AM stations.  These classes are A, B, C, and D.  Generally, all U.S. records will have both a Domestic Class and a Region 2 Class.  For U.S. stations, the Region 2 Class can be derived from the Domestic Class.  Therefore, we explain how to derive the Domestic Class first.

The AM band frequencies are divided into three categories: Clear, Regional, and Local channels.  The allowable classes depend on a station's frequency, in addition to other variables.  On the Clear channels certain stations are specifically classified as Class A stations or as Class B stations.  The other stations have their class determined by their frequency.

Classes of AM stations are defined as follows:

  • Class A Station.  A Class A station is an unlimited time station (that is, it can broadcast 24 hours per day) that operates on a clear channel.  The operating power shall not be less than 10 kilowatts (kW) or more than 50 kW.
     
  • Class B Station.  A Class B station is an unlimited time station.  Class B stations are authorized to operate with a minimum power of 0.250 kW (250 watts) and a maximum power of 50 kW.  (If a Class B station operates with less than 0.250 kW, the RMS must be equal to or greater than 107.5 mV/m at 1 km at the actual power.)  If the station is authorized to operate in the expanded band (1610 to 1700 kHz), the maximum power is 10 kW.
     
  • Class C Station.  A Class C station is an unlimited time station that operates on a local channel.  The power shall not be less than 0.25 kW nor more than 1 kW.  Class C stations that are licensed to operate with 0.100 kW may continue to operate as licensed.
     
  • Class D Station. A Class D station operates either daytime, limited time, or unlimited time with a nighttime power less than 0.250 kW and an equivalent RMS antenna field less than 107.5 mV/m at 1 km at the actual power.  Class D stations shall operate with daytime powers not less than 0.250 kW nor more than 50 kW. NOTE: If a station is an existing daytime-only station, its class will be Class D.

Clear, Regional, and Local Channels, and
Steps to Follow to Determine the Domestic Class

If you don't want to use the easy way to determine the station's domestic class (via the AM Query), here's the steps to follow to determine the class. A table of which frequencies are Clear, Regional, or Local is included below.

  • 1.  Determine which frequency the station is on (or is proposing) and also determine whether the station is one of the ones with a specifically defined class (see the right column in the table below).  Following is a list, by frequency, which lists the specific Class A or Class B stations, along with the available classes for the other stations:
Channel Type Frequency
(kHz)
Available
Classes
Assignment
Old class designation in ( )
---- 530 ---- In the USA, reserved for low power
AM Travelers' Information Stations
Clear 540 A,B,D  
Regional 550 B,D  
Regional 560 B,D  
Regional 570 B,D  
Regional 580 B,D  
Regional 590 B,D  
Regional 600 B,D  
Regional 610 B,D  
Regional 620 B,D  
Regional 630 B,D  
Clear 640 A,B,D KFI, Los Angeles, CA: Class A (I-A)
KYUK, Bethel, AK: Class A (I-N)
Clear 650 A,B,D WSM, Nashville, TN: Class A (I-A)
KENI, Anchorage, AK: Class A (I-N)
Clear 660 A,B,D WFAN, New York, NY: Class A (I-A)
KFAR, Fairbanks, AK: Class A (I-N)
Clear 670 A,B,D WSCR, Chicago, IL: Class A (I-A)
KDLG, Dillingham, AK: Class (I-N)
KBOI, Boise, Idaho: Class B (II-A)
Clear 680 A,B,D KNBR, San Francisco, CA: Class A (I-B)
KBRW, Barrow, AK: Class A (I-N)
Clear 690 A,B,D  
Clear 700 A,B,D WLW, Cincinatti, OH: Class A (I-A)
KBYR, Anchorage, AK: Class A (I-N)
Clear 710 A,B,D WOR, New York, NY: Class A (I-B)
KIRO, Seattle, WA: Class A (I-B)
Clear 720 A,B,D WGN, Chicago, IL: Class A (I-A)
KOTZ, Kotzebue, AK: Class A (I-N)
KDWN, Las Vegas, NV: Class B (II-A)
Clear 730 A,B,D  
Clear 740 A,B,D  
Clear 750 A,B,D WSB, Atlanta, GA: Class A (I-A)
KFQD, Anchorage, AK: Class A (I-N)
Clear 760 A,B,D WJR, Detroit, MI: Class A (I-A)
Clear 770 A,B,D WABC, New York, NY: Class A (I-A)
KKOB, Albuquerque, NM: Class B (II-A)
Clear 780 A,B,D WBBM, Chicago, IL: Class A (I-A)
KNOM, Nome, AK: Class A (I-N)
KKOH, Reno, NV: Class B (II-A)
Regional 790 B,D  
Clear 800 A,B,D  
Clear 810 A,B,D KGO, San Francisco, CA: Class A (I-B)
WGY, Schenectady, NY: Class A (I-B)
Clear 820 A,B,D WBAP, Fort Worth, TX: Class A (I-A)
KCBF, Fairbanks, AK: Class A (I-N)
Clear 830 A,B,D WCCO, Minneapolis, MN: Class A (I-A)
Clear 840 A,B,D WHAS, Louisville, KY: Class A (I-A)
Clear 850 A,B,D KOA, Denver, CO: Class A (I-B)
KICY, Nome, AK: Class A (I-N)
Clear 860 A,B,D  
Clear 870 A,B,D WWL, New Orleans, LA: Class A (I-A)
Clear 880 A,B,D WCBS, New York, NY: Class A (I-A)
KRVN, Lexington, NE: Class B (II-A)
Clear 890 A,B,D WLS, Chicago, IL: Class A (I-A)
KBBI, Homer, AK: Class A (I-N)
KDXU, St. George, UT: Class B (II-A)
Clear 900 A,B,D  
Regional 910 B,D  
Regional 920 B,D  
Regional 930 B,D  
Clear 940 A,B,D  
Regional 950 B,D  
Regional 960 B,D  
Regional 970 B,D  
Regional 980 B,D  
Clear 990 A,B,D  
Clear 1000 A,B,D WMVP, Chicago, IL: Class A (I-A)
KOMO, Seattle, WA: Class A (I-B)
Clear 1010 A,B,D  
Clear 1020 A,B,D KDKA, Pittsburgh, PA: Class A (I-A)
KCKN, Roswell, NM: Class B (II-A)
KVNT, Eagle River, AK: Class A (I-N)
Clear 1030 A,B,D WBZ, Boston, MA: Class A (I-A)
KTWO, Casper, WY: Class B (II-A)
Clear 1040 A,B,D WHO, Des Moines, IA: Class A (I-A)
Clear 1050 A,B,D  
Clear 1060 A,B,D KYW, Philadelphia, PA: Class A (I-B)
Clear 1070 A,B,D KNX, Los Angeles, CA: Class A (I-B)
Clear 1080 A,B,D WTIC, Hartford, CT: Class A (I-B)
KRLD, Dallas, TX: Class A (I-B)
KOAN, Anchorage, AK: Class A (I-N)
Clear 1090 A,B,D KAAY, Little Rock, AR: Class A (I-B)
WBAL, Baltimore, MD: Class A (I-B)
Clear 1100 A,B,D WTAM, Cleveland, OH: Class A (I-A)
KNZZ, Grand Junction, CO: Class B (II-A)
Clear 1110 A,B,D WBT, Charlotte, NC: Class A (I-B)
KFAB, Omaha, NE: Class A (I-B)
Clear 1120 A,B,D KMOX, St. Louis, MO: Class A (I-A)
KPNW, Eugene, OR: Class B (II-A)
Clear 1130 A,B,D KWKH, Shreveport, LA: Class A (I-B)
WBBR, New York, NY: Class A (I-B)
Clear 1140 A,B,D WRVA, Richmond, VA: Class A (I-B)
Regional 1150 B,D  
Clear 1160 A,B,D KSL, Salt Lake City, UT: Class A (I-A)
Clear 1170 A,B,D KFAQ, Tulsa, OK: Class A (I-B)
WWVA, Wheeling, WV: Class A (I-B)
KJNP, North Pole, AK: Class A (I-N)
Clear 1180 A,B,D WHAM, Rochester, NY: Class A (I-A)
KOFI, Kalispell, MT: Class B (II-A)
Clear 1190 A,B,D KEX, Portland, OR: Class A (I-B)
Clear 1200 A,B,D WOAI, San Antonio, TX: Class A (I-A)
Clear 1210 A,B,D WPHT, Philadelphia, PA: Class A (I-A)
KGYN, Guymon, OK: Class B (II-A)
Clear 1220 A,B,D  
Regional 1230 B Stations in AK, HI, PR, and the U.S. VI
Local 1230 C Stations in coterminous 48 states
Regional 1240 B Stations in AK, HI, PR and the U.S. VI
Local 1240 C Stations in coterminous 48 states
Regional 1250 B,D  
Regional 1260 B,D  
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 AK, HI, PR, and the U.S. VI
Local 1340 C Stations in the coterminous 48 states
Regional 1350 B,D  
Regional 1360 B,D  
Regional 1370 B,D  
Regional 1380 B,D  
Regional 1390 B,D  
Regional 1400 B Stations in AK, HI, PR, and the U.S. VI
Local 1400 C Stations in the coterminous 48 states
Regional 1410 B,D  
Regional 1420 B,D  
Regional 1430 B,D  
Regional 1440 B,D  
Regional 1450 B Stations in AK, HI, PR, and the U.S. VI
Local 1450 C Stations in the coterminous 48 states
Regional 1460 B,D  
Regional 1470 B,D  
Regional 1480 B,D  
Regional 1490 B Stations in AK, HI, PR, and the U.S. VI
Local 1490 C Stations in the conterminous 48 states
Clear 1500 A,B,D WFED, Washington, DC: Class A (I-B)
KSTP, St. Paul, MN: Class A (I-B)
Clear 1510 A,B,D WLAC, Nashville, TN: Class A (I-B)
KGA, Spokane, WA: Class A (I-B)
Clear 1520 A,B,D WWKB, Buffalo, NY: Class A (I-B)
KOKC, Oklahoma City, OK: Class A (I-B)
Clear 1530 A,B,D KFBK, Sacramento, CA: Class A (I-B)
WCKY, Cincinatti, OH: Class A (I-B)
Clear 1540 A,B,D KXEL, Waterloo, IA: Class A (I-B)
Clear 1550 A,B,D  
Clear 1560 A,B,D KNZR, Bakersfield, CA: Class A (I-B)
WFME, New York, NY: Class A (I-B)
Clear 1570 A,B,D  
Clear 1580 A,B,D  
Regional 1590 B,D  
Regional 1600 B,D  
Regional 1610 B  
Regional 1620 B  
Regional 1630 B  
Regional 1640 B  
Regional 1650 B  
Regional 1660 B  
Regional 1670 B  
Regional 1680 B  
Regional 1690 B  
Regional 1700 B  
 
  • 2. If the station is specifically listed in the table on the actual frequency in the actual city, then the Domestic Class for the station is defined on the above list.  (Call sign changes don't matter, the classification remains with the station, not the call sign.)

    Note that all the former Class I-N stations are located in Alaska, while all the former Class I-A and former Class I-B stations are located only in the coterminous 48 states. Only in Alaska might it be possible to assign new Class A stations.

  • 3. If the station of interest is not specifically listed above on the actual frequency in the actual city, the Domestic Class must be determined from the available classes for the frequency:
     
    • If the available classes are A, B, and D, then the Domestic Class will be Class B.  It cannot be Class A because all of the Class A stations are listed above.  It cannot be Class D because the Commission will not authorize new Class D stations (unless the station had been previously licensed as Class B and the station is downgrading to its nighttime operation to Class D.)

      If the station is an existing daytime-only station, the class will be Class D.

    • If the available classes are B and D, then the Domestic Class will be Class B.  It cannot be Class D because the Commission will not authorize new Class D stations (unless the station had been previously licensed as Class B and the station is downgrading to its nighttime operation to Class D.)

      If the station is an existing daytime-only station, the class will be Class D.

    • If the available classes are B and C, then the Domestic Class will generally be Class C.  However, if the station is in Alaska, Hawaii, Puerto Rico or the U.S. Virgin Islands, then the Domestic Class is Class B.

  • 4. The rules adopted in MM Docket 87-267 allow existing unlimited-time Class B (formerly Class II and III) stations to voluntarily reclassify their nighttime operations to Class D if they find it advantageous to do so.  This is the ONLY instance where new Class D stations are allowed.  [ Existing Class D daytime-only stations will remain so classified. ]

An AM station can have only one licensed class.  The licensed daytime class cannot be different than the licensed nighttime class. If the station is downgrading its nighttime operation to Class D, then the construction permit will have a different class than the license.  Once the construction permit becomes licensed as Class D, then any licensed daytime record will be changed to Class D also.

Once the Domestic Class has been obtained, the Region 2 Class is easily determined:

The Region 2 Class

Domestic Class              Region 2 Class

A              A
B              B
C              C
D              B
 

Old to New Class Conversions

Because the old classification system for AM broadcast stations will be encountered in older documents pertaining to AM radio, we have provided this conversion table for your convenience:

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

Note: The "S" in Class II-S or III-S denoted secondary operation, for the purposes of nighttime operation.


Information about AM broadcast radio stations is available at the Audio Division on the FCC's website, and at Broadcast Radio Links.

FCC > Media Bureau > Audio Division, (202)-418-2700.

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Updated:
Thursday, June 3, 2021