自制电话机电子振铃器李学海振铃器是电话机的重要组成部分。当对方打来电话时，振铃器发出铃声，提醒被叫用户及时摘机应答。早年生产的电话机全部采用电磁结构的极化铃，它体积笨重、铃声刺耳、维修困难。随着微电子技术的飞速发展，近些年生产的电话机，绝大多数采用了... Home phone electronic ringer Lee Hsueh-ring ringer is an important part of the phone. When the other party called, the ringer ringing to remind the called user pick up the phone promptly answer. Early production of telephone use electromagnetic polarization of all the bell structure, it bulky, jingle ringing, maintenance difficulties. With the rapid development of microelectronic technology, the production of telephone in recent years, the vast majority adopted ...