Remote control

From ArticleWorld

A remote control is an electronic device that is used for the operation of a machine from an isolated location. It is particularly popular in television systems and other electronic items like stereo systems and DVD players. Most remote control devices are handheld objects with an arrangement of buttons for determining required settings in a particular system. Majority of the possible functions are usually provided in a remote control device with only a few of the available functions accessible from the main device itself. While most devices use infrared (IR) signals, a few remote control devices make use of radio waves.

Remote controls - A brief history

The concept of remote controls was first brought by Nikola Tesla in 1893. The new idea continued to be studied till 1932 when the first remote-controlled model airplane was flown. It was used by the Germans during the Second World War and was first brought to use in television sets in the 1950s by Zenith Radio Corporation. It was initially implemented using a wire to communicate with the TV. In a move to get rid of the cumbersome system of using long wires, the company developed a light-based alternative in which a steady beam of light would have to be pointed accurately at the receiver. Further developments saw the introduction of ultrasonic waves being used to control television devices, which had its own flaws.

With the development of semiconductor technology in the 1980s methods for emitting and receiving infrared radiation were developed, with the result that remote radio technologies came to the fore. These methods are still in use today, with further improvisations seeing the use of Bluetooth as well.

Remote controls - The technique

Majority of remote control devices for electronic items use an infrared diode to give out a beam of light to be transmitted to the device being controlled. The signal in a multi-channeled remote requires the modulation of a carrier signal with the signals of different frequencies. The necessary signals are given to the device after they are demodulated. Procedures are implemented in the digital form in most applications today.

Major applications of remote controls

Apart from the normal home and office-based electronic appliances for which remote controls are used, these devices find use in high-voltage substations and HVDC plants. Nuclear power plants also make use of remote control, where conditions are extremely hazardous for human operators. Most often, PLC controls are put to use in such situations.

This technology is also used in space exploration though it may not be feasible in vast distances where delays are likely to spiral up. Another widely popular field where remote control technology finds use is in the military. A large number of munitions make use of this concept to accurately strike at the enemy.