Working principle of fixed telephone

The working principle of fixed telephone is that the current and voltage on the telephone line are modulated by the microphone in the telephone through the vibration of sound, that is, the sound is converted into a voltage signal, which is transmitted to the other end of the telephone through the telephone line, and then the voltage signal is converted into a sound signal by the microphone.

A simple telephone loop includes a receiver and a transmitter, a power supply and a line, all of which are connected in series. In fact, the fixed telephone should also include ringing line, dialing loop and caller ID function, and the telephone should also cooperate with the exchange of the telecommunication bureau to complete the dialing work.

Extended data:

Use of fixed telephone:

Most users of fixed telephones are enterprises, shops and rural areas. Fixed telephone still exists as office telephone for a long time because of its high integrity, good confidentiality and low replacement frequency.

For families, the fixed telephone, like a house, is a proof of stability and a means of communication for family stability. Some people may argue that the home fixed telephone exists because the network and the fixed telephone are in a binding state, and the fixed telephone has to be kept in order to access the Internet. Moreover, telegrams replace letters, fixed telephones replace telegrams, and mobile phones squeeze fixed telephones. Technological innovation makes the update of communication tools inevitable.

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