South Korea’s Christian Broadcasting System (CBS/기독교방송) is a nationwide radio radio network. Beginning with HLKY in Seoul in 1954 on AM, the network spread to five stations by 1961 (Seoul, Iri (now Jeonju), Gwangju, Daegu, and Pusan.) Today the radio network consists of the original AM and numerous FM outlets serviced by three network programming feeds and 13 regional stations.
Over the years they sent QSL cards for my reception reports of all five of the AM outlets. I visited all of the AM stations except the one in Gwangju.
For audio clips scroll down below the QSLs.
HLKP 1404 Busan 
HLKP 1404 Pusan 
HLKT 1251 Daegu from 1976 
HLKT 1251 Daegu from 1976 
HLKY 837 Seoul 1984 
HLKY 837 Seoul 1984 
HLKY 837 Seoul 1990 
HLKY 837 Seoul 1990 
HLCL 999 Gwangju 1991 
HLCL 999 Gwangju 1991 
HLKT 1251 Daegu 1991 
HLKT 1251 Daegu 1991 
HLCM 1314 Iri 1990 
HLCM 1314 Iri 1990
AUDIO CLIPS
14 June 1990 9:00 AM KST. (0000 UTC)
CBS Campaign, weather, top of hour identification, ad for Hyundai Electronics, time pips sponsored by Hyundai Electronics, and new program.
22 June 1990 4:55 AM KST (1955 UTC)
Full Sign On
18 November 1989 9:00 AM (2300 UTC)
End of ad for a Boiler, program preview, TOH identification, CBS song, time pips and local programming.
17 June 1990 3:00 PM (0600 UTC)
Program preview, TOH identification, spot for Hyundai Electronics, time pips, more programming.