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电话机的拨号方式分为两种:脉冲拨号和双音频拨号。脉冲拨号由于拨号速度慢,信号易产生畸变,并且容易错号,或产生线间干扰等诸多缺点,必将被发号快速、准确,易实现多项特种服务的双音频拨号所代替。如果您手头的电话机为脉冲拨号方式,不妨按下述两种方法尝试一下,将其改为双音频拨号方式。 方法一 机内改动法 脉冲拨号电路与双音频拨号电路的区别主要有两点:一是采用的发号集成电路不同,脉冲拨号电路采用脉冲发号专用集成电路,双音频拨号电路采用双音频发号专用集成电路;二是外围电路也略有不同,一个外接的是脉冲开关电路;另一个外接的是双音频放大电路。这样,
Telephone dialing is divided into two types: pulse dialing and dual tone dialing. Pulse Dialing Due to the slow dialing, the signal is easy to produce distortion, and easy to wrong number, or produce a lot of shortcomings between line interference, will be issued by the number of fast, accurate, easy to achieve a number of special services dual tone dial instead. If your handset is a pulse dialing method, try the following two methods to change it to dual tone dialing mode. Method a machine change pulse dialing circuit and dual tone dialing circuit the difference is mainly two points: First, the use of the integrated circuit is different, the pulse dialing circuit using a pulse-specific integrated circuits, dual-tone dial-up circuit using dual audio No. special integrated circuit; the second is the peripheral circuit is also slightly different, an external pulse switching circuit; another external double audio amplifier. such,