One of the many great historical resources now online is World Radio History’s collection of Broadcasting Yearbooks.
I think it’s interesting to plot out what stations existed when, and what the offerings were at various points in history. Here, I look at the radio dial in Duluth-Superior in the 1950s and 1960s, though the yearbooks didn’t usually specify format, only network affiliation. (An asterisk indicates the station is licensed to Superior.)
1951 Broadcasting Yearbook
610 KDAL (CBS)
710 WDSM* (ABC)
1080 WREX (MBS) 10kW/5kW, established 1948
1320 WEBC (NBC)
1954 Broadcasting Yearbook
610 KDAL (CBS)
710 WDSM* (ABC/MBS)
1320 WEBC (NBC)
(WREX is no longer listed)
1955 Broadcasting Yearbooks
560 WEBC (NBC)
610 KDAL (CBS)
710 WDSM* (ABC/MBS)
1958 Broadcasting Yearbook
560 WEBC (NBC)
610 KDAL (CBS)
710 WDSM* [no network listed]
1320 WQMN* construction permit
1959 Broadcasting Yearbook
560 WEBC [network no longer listed]
610 KDAL (CBS)
710 WDSM (NBC)
1320 WQMN
89.1 KUMD [construction permit]
1960 Broadcasting Yearbook
560 WEBC
610 KDAL (CBS)
710 WDSM* (NBC)
1320 WQMN* (MBS)
89.1 KUMD [construction permit]
1961 Broadcasting Yearbook
560 WEBC
610 KDAL (CBS)
710 WDSM* (NBC)
970 WIGL* [construction permit]
1320 WQMN* (MBS)
89.1 KUMD
1963 Broadcasting Yearbook
560 WEBC
610 KDAL (CBS)
710 WDSM* (NBC)
970 WIGL*
1320 WQMN* (MBS)
1390 KAOH
89.1 KUMD
1965 Broadcasting Yearbook
560 WEBC
610 KDAL (CBS)
710 WDSM* (NBC)
970 WIGL*
1270 WWJC*
1320 WAKX* (MBS)
1390 KAOH
89.1 KUMD
105.1 WWJC-FM* [construction permit]
1967 Broadcasting Yearbook
560 WEBC (ABC)
610 KDAL (CBS)
710 WDSM* (NBC)
970 WIGL*
1270 WWJC*
1320 WAKX* (MBS)
1390 KAOH
89.1 KUMD
91.3 WSSU*
105.1 WWJC-FM* 75% simulcast of WWJC(AM)
1968 Broadcasting Yearbook
560 WEBC (ABC)
610 KDAL (CBS)
710 WDSM* (NBC)
970 WIGL*
1270 WWJC*
1320 WAKX* (MBS)
1390 KAOH
89.1 KUMD
91.3 WSSU*
94.9 [construction permit; Channel 10, Inc.]
105.1 WWJC-FM* 75% simulcast of WWJC(AM)
1969 Broadcasting Yearbook
560 WEBC (ABC/MBS)
610 KDAL (CBS)
710 WDSM (NBC)
970 WAKX* (ABC)
1270 WWJC* (ABC)
1390 KAOH
89.1 KUMD
91.3 WSSU*
94.9 WDIO-FM [construction permit]
105.1 WWJC-FM* 25% simulcast of WWJC(AM)
(1320 no longer listed)
Of course, this is only the very surface of a very active period in history. WEBC became a legendary Top 40 outlet around the time it moved to 560, later followed in the format by WIGL and WAKX. (WAKX eventually assumed WIGL’s facility and returned its original license.)
The late Roger Johnson’s “A Technological History of WEBC Radio” documents not only WEBC’s engineering history, but its programming and that of other stations in the market.