What is a digital switch
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Experts answer: "exchange" and "switch" first originated in the telephone communication system (PSTN). We used to often see in films or television movies often see some old people in the phone and shake a few crazy (note not a dial-up), and then said: Tell me the XXX, was asked if service operator Will end after the corresponding thread inserted in the terminal to be connected, you can call. In fact, this is the most primitive telephone switching system, except that it is a manual telephone exchange systems is not automatic, nor is it today to talk about the program-controlled switches, but we're talk about the program-controlled switchboard was also during this Dianhua Switch technology evolved. Since 1876, the United States Bell invented the telephone, along with the growing social needs and technological capabilities continue to improve, telephone switching technology in the rapid change and evolving. The process can be divided into three stages: manual switching, electromechanical switching and electronic switching. As early as 18 78 years appeared artificial switch, if it is carried out with operator services continue, obviously its efficiency is very low. 15 years after the advent of stepping switch system, which marks the switching from the artificial era to enter the era of mechanical and electrical switching. This switch is "direct control" mode, the user can dial the phone Pulse device to do directly control the stepping movements and rotary connecting movement. Between users to automatically follow. Although the switch realization of the automatic connection, but there are slow, low efficiency, noise and mechanical wear big and serious shortcomings. Until 1938, invented the crossbar (crossbar) switch Only a partial solution to these problems, relative to the step-by-step system switch, it has two important improvements: 1. Using relay control of the pressure contact with a substantial connection array instead of stepping movements wiring devices, thereby reducing wear and noise, improve the reliability and continuation rates; 2. the transition from direct control to indirect control of party Type, so the user does not directly control the dial pulse wiring device moves, the hair initially recorded the receipt, storage, and then drive through the markers, wiring devices, in order to complete the user indirectly added. This indirect control method to control part of the road and then separated, increased flexibility and control efficiency and speed. As the vertical and horizontal System switch has a series of advantages, and therefore the development of its telephone exchange plays an important role, has been widely used, until now, in many countries and a few areas of China are still using public telephone communication network switch with vertical and horizontal semiconductor devices and the birth of computer technology and the rapid development of Violently impact the traditional electromechanical switching fabric, so go electronic. American Bell in 1965 through hard work produced the world's first commercial stored program controlled electronic switch (No.1ESS), this result marks the era of telephone exchanges from the Electrical and leap into the electronic age, Place to exchange technology of the times change. As electronic switch is small, fast, easy and reliable service to provide effective advantages, caused great interest in the world. In the development process have developed various types of electronic switches.
Experts answer: "exchange" and "switch" first originated in the telephone communication system (PSTN). We used to often see in films or television movies often see some old people in the phone and shake a few crazy (note not a dial-up), and then said: Tell me the XXX, was asked if service operator Will end after the corresponding thread inserted in the terminal to be connected, you can call. In fact, this is the most primitive telephone switching system, except that it is a manual telephone exchange systems is not automatic, nor is it today to talk about the program-controlled switches, but we're talk about the program-controlled switchboard was also during this Dianhua Switch technology evolved. Since 1876, the United States Bell invented the telephone, along with the growing social needs and technological capabilities continue to improve, telephone switching technology in the rapid change and evolving. The process can be divided into three stages: manual switching, electromechanical switching and electronic switching. As early as 18 78 years appeared artificial switch, if it is carried out with operator services continue, obviously its efficiency is very low. 15 years after the advent of stepping switch system, which marks the switching from the artificial era to enter the era of mechanical and electrical switching. This switch is "direct control" mode, the user can dial the phone Pulse device to do directly control the stepping movements and rotary connecting movement. Between users to automatically follow. Although the switch realization of the automatic connection, but there are slow, low efficiency, noise and mechanical wear big and serious shortcomings. Until 1938, invented the crossbar (crossbar) switch Only a partial solution to these problems, relative to the step-by-step system switch, it has two important improvements: 1. Using relay control of the pressure contact with a substantial connection array instead of stepping movements wiring devices, thereby reducing wear and noise, improve the reliability and continuation rates; 2. the transition from direct control to indirect control of party Type, so the user does not directly control the dial pulse wiring device moves, the hair initially recorded the receipt, storage, and then drive through the markers, wiring devices, in order to complete the user indirectly added. This indirect control method to control part of the road and then separated, increased flexibility and control efficiency and speed. As the vertical and horizontal System switch has a series of advantages, and therefore the development of its telephone exchange plays an important role, has been widely used, until now, in many countries and a few areas of China are still using public telephone communication network switch with vertical and horizontal semiconductor devices and the birth of computer technology and the rapid development of Violently impact the traditional electromechanical switching fabric, so go electronic. American Bell in 1965 through hard work produced the world's first commercial stored program controlled electronic switch (No.1ESS), this result marks the era of telephone exchanges from the Electrical and leap into the electronic age, Place to exchange technology of the times change. As electronic switch is small, fast, easy and reliable service to provide effective advantages, caused great interest in the world. In the development process have developed various types of electronic switches.
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