What is the dialing principle of the old dial-up phone?

Principle: Each cell of the telephone dial is a pulse. One dial 1 and nine dial 9, that is, you can hear 9 clicks. Each corresponding position is opened once, and the missed position is broken. The next frame is another pulse, and 0 is 10 pulses.

For ordinary phones, you can make a call directly by pressing the switch to hang up the phone without pressing the button. For example, continuous shooting dialed 8 times, continuous shooting 7 times after the suspension, continuous shooting 9 times after the suspension, continuous shooting 10 times after the suspension, and continuous shooting 5 times after the suspension.

Continuous shooting suspended six times, continuous shooting suspended six times and continuous shooting suspended three times. If the operation is correct, the call will be placed. Every beat is a pulse.

Extended data

Wired telephone:

The telephone has the function of converting the sound wave of the terminal into an electronic signal, transmitting it to a distant party through a telephone line, regenerating the electronic signal transmitted by the other party into voice (sound wave), making it talk, and sending a signal (dialing pulse) selectable from multiple parties to inform the other party of the calling sound.

A telephone consists of a transmitter that converts voice into current and sends it to a telephone line, a receiver that converts current sent by the other party into voice, a dial or button of the calling party, a ringtone that sends a call tone, and a line network that connects these to the telephone line to perform its functions. There is a small box filled with carbon particles in the transmitter, with a thin and hard aluminum alloy vibrating plate in front.

The vibrating plate vibrates according to the sound, vibrates the carbon particles, and the carbon particles conduct current. With the contact degree of particles, the resistance changes, resulting in voice current. After the receiver receives the voice current of the other party, it generates magnetic force on the coil caused by the voice current, vibrates the iron vibrating plate and makes sound.

Baidu Encyclopedia-Rotary Dialing Phone