How do telephones work? - Presentation

Telephones are fascinating devices that have transformed the way we communicate. To understand how a landline telephone works, we delve into the process of converting sound into an electrical signal. When you speak into a landline phone, your voice creates sound waves that are transformed into electrical signals by the phone's components. These signals travel through a network of cables and exchanges, reaching the recipient's phone where they are converted back into sound waves, enabling the listener to hear your voice. The system has evolved remarkably from the days when it could take weeks to send a message, to the current instant connections we make across vast distances.

Mobile telephones, on the other hand, operate on a different principle. They act as both radio transmitters and receivers, similar to walkie-talkies but with far more sophistication. When you speak into a mobile phone, your voice is converted into an electrical signal, which is then transmitted as radio waves. These waves are received by a nearby phone mast and relayed across a network of masts until they reach the mast closest to the person you're calling. Their phone then receives these radio waves and converts them back into sound. The cellular network is divided into hexagonal 'cells', each with its own mast, allowing for seamless communication even when you're on the move, as your call is handed off from one mast to another without interruption. This intricate network enables us to chat effortlessly with someone across town or even across the world.