... function:volume,FM frequency TF card,USB,AUX Decoder Board with FM radioStrang decoder: TF card,USB,AUX ... MP3 Decoder Board, pcb board &ABS board, fm radio and digital screen display, with ... functions PLAY/PAUSE at USB/SD state; Short press it to search and save channels.2.“VOL-”: ... at the standby mode when you press this button. SD card decoder board: SW-005 TF card,USB,AUX ...