 DZFM, later renamed their call letters to DZSR on 738 kHz, however the station's callsign was reverted to DZFM as a courtesy to the original owner of the frequency, Frederick Marquardt, an American national who donated the 738 kHz frequency to the Philippine government.On March 1, 1996, 5 years after Marquardt's death, Sports Radio's frequency was moved from 738 kHz (now occupied by Radyo ng Bayan) to 918 kHz and changed their call letters back to DZSR under Memorandum Order No.329 (Presidential Order No.