WGPA [SEP] licensed to broadcast to
WGPA
WGPA (1100 kHz) is a Class D daytimer radio station, licensed to Bethlehem, Pennsylvania, and serving the Lehigh Valley. It is owned by CC Broadcasting, LLC. It airs a Full-Service radio format as "Ameripolitan," consisting of classic country music, rockabilly, oldies and polka music.
Because AM 1100 is a clear channel frequency, WGPA must sign off at night to protect WTAM in Cleveland, the Class A station on 1100 kHz. (Radio waves travel farther at night
simulcast during daylight hours with sister station WGPA. The AM 1100 station is authorized by the Federal Communications Commission to broadcast only from sunrise to sunset, so programming continued on FM station until 11 PM. At that time WGPA-FM used a sub-carrier to broadcast instrumental beautiful music from reel-to-reel tapes for playing over paging systems inside retail businesses. Eventually, that same beautiful music sound was airing on WGPA-FM. 
In 1973, when WGPA-AM and FM were sold by the Globe-