采用锁相环技术（PLL技术）保证发射/接收的稳定性。发射采用三点发射，有效避开相邻耳机的相互干扰,接收采用手动调谐方式。无障碍距离：30米发射机工作频率：85MHZ-86MHZ 接收机工作频率：84MHZ-87MHZ * With PLL technology to ensure the transmitting and receiving reliable and stable. * Three transmitting frequency points can avoid interference among headphones. * Receiving by automatic searching *Transmitting frequency range:85MHz---86MHz * Receiving frequency range:84MHz---87MHz