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一、引言电话机是一种声电转换器,在自动电话网络中是电话交换机(简称交换机)的终端设备,起着听、讲、收、发等作用。打电话时。发话人总是先拎起电话机听筒,听到拨号音后使用号盘拨打受话人电话号码。拎起听筒是发话人向交换机申请使用电话,听到拨号音是交换机接受申请后发来的回响,拨打受话人电话号码是请求交换机把该电话的线路接通。拨打电话机号盘数字是它向交换机发送电脉冲,只要发送的电脉冲数同号盘上数字相一致(数字0应发10个电脉冲),且脉冲周期和断续比符合交换机接口要求,交换机便会按发话人拨打的电话号码,自动把受话人线路接通,并同时发出低频振铃或音乐信号。本文将要介绍的电话机号盘脉冲信号测试仪是按
I. INTRODUCTION Telephone is a kind of sound and electricity converter, which is a terminal equipment of telephone exchange (abbreviated as switch) in automatic telephone network. It plays the roles of listening, speaking, receiving and sending. When calling The caller always picks up the handset and dials the caller’s phone number using the dial pad after hearing the dial tone. Pick up the handset is the caller to the switch to use the phone, hear the dial tone is the switch to accept the application sent back the response, call the recipient phone number is asking the switch to the line connected to the phone. Dial the number of telephone dial is it sends electrical pulses to the switch, as long as the number of electrical pulses sent consistent with the numbers on the dial (digital 0 should be issued 10 electrical pulses), and pulse cycle and intermittent than in line with the switch interface requirements, The switch will automatically dial the receiver’s line according to the telephone number dialed by the caller and simultaneously send a low-frequency ringing or music signal. This article will introduce the telephone dial pulse signal tester is pressed