Before the advent of mobile phones, outdoor enthusiasts have been using walkie-talkies for two-way communication. Nowadays, these devices are mainly used in areas lacking mobile phone reception capabilities.
Compared with other communication methods in the field, walkie-talkies have the advantages of being easy to use and low cost, which almost eliminates barriers to entry. Nevertheless, due to the line of sight function, the range of the walkie-talkie is still limited. Other handheld communicators used in remote areas use satellites, repeaters, or can bounce radio signals out of the atmosphere.
People communicating via walkie-talkies must first ensure that they share the same channel or frequency band. Their earpieces have been set to receive, so the microphone and speaker are set as speakers. When no one is speaking, the device may be broadcasting
The sound of static electricity is like the detuned sound in the radio. When someone wants to talk, they simply press the push-to-talk button to force their speaker to switch to the microphone function, thereby eliminating static electricity.
When they speak, their words are converted into radio waves and broadcast through pre-arranged channels. Radio waves fall into the electromagnetic spectrum, so they travel at the speed of light (186,000 miles per second) and are instantly felt by other earpieces, and then converted back to vibration or fluctuating current, and the sound of the speaker is broadcast by the speaker.
After the speaker finishes speaking, they say "past" to let the audience know that they have finished speaking, then release the push-to-talk button and the earpiece returns to the earpiece mode.
The walkie-talkie is a two-way radio, which means that unlike ordinary radios, it can send and receive information. Since the two functions use the same channel, only one person can speak at a time.
To avoid interference from other two-way radio users, most modern systems allow use on multiple channels. For this, radio transmitters must be able to generate waves of different frequencies.
A group of people using walkie-talkies to talk to each other must tune into the same frequency band, the channel. Their radios are all "receiving", so their microphone/speaker unit is working as a speaker and may emit static hiss, which is a bit like a regular radio that is not tuned into any particular station. When someone wants to talk to other people, they hold down the push-to-talk button on their phone. When the speaker is switched to the microphone, the sound of the radio becomes quiet. When they speak, their words are converted into radio waves and beams are emitted on pre-arranged channels (usually 460 MHz in the United States and 446 MHz in Europe). Since radio waves are part of the electromagnetic spectrum, they travel at the speed of light (300,000 kilometers/second or 186,000 miles/second), so other mobile phones can receive waves almost instantly. The radio waves are converted back to fluctuating currents, and the speakers use these currents to reproduce the voice of the speaker. After the speaker finishes speaking, he or she says "end" (indicating that my speech is over), and then releases the push-to-talk button. The radio now switches to the recycling listening mode, and other people can talk.
Ordinary walkie-talkies will only receive broadcast sound or music from radio stations, while walkie-talkies are two-way broadcasts: you can talk and listen (send and receive). The main disadvantage is that two things use the same channel, so only one person can speak at a time. When communication devices work in this way, they are described as half-duplex (a single channel allows communication in only one direction at any time), rather than full-duplex (you can talk and listen at the same time). On the phone).