Complex sentence: The station broadcast a Big Band format with the WRHY call sign until August 12,1983, when the station switched call signs to WHTF and its format to Contemporary Hit Radio as "Rock 92".
Split into simpler sentences: The station broadcasted a Big Band format with the WRHY call sign prior to August 12,1983. On that day, the station switched call signs to WHTF and format to Contemporary Hit Radio as "Rock 92".