Remote Control and Radio

In the earliest days of communication technology, electrical signals were transmitted through wires from one end to another. This limited the distance between the users. It also meant that the devices had to be in a fixed position at all times. The clarity of the sound was not that good either because of noise and interference. Despite these challenges, the technology became highly popular because it opened up a world of possibilities. The invention of the radio brought a new age in which wireless communication is the norm. Today, people can use a tiny wireless radio earpiece to listen to signal transmissions.

Learn more about radio earpiece


Radio Technology


Radio comes from the Latin word radius to imply a radiated sound coming from a source. This technology uses radio waves in the air to carry information. This can be anything from data, sound or video. The properties of the waves are changed in a precise manner to signify different things. The transmitter blasts out this signal using high energy. When a receiver detects this, the oscillating fields will induce current to run in the conductor. There is a built-in decoder to extract the information and turn it back into the original form. Voice, for instance, can be extracted from the waves.


Frequency Modulation


Modulation can occur in different ways because various properties can be changed. The most basic shape of any wave is a sinusoid which goes smoothly up and down in continuous fashion. This can be changed into square waves, for instance, for digital communications when there are only two signals on and off. Their properties include amplitude, phase, frequency, and pulse width. Amplitude is the height or strength of the wave. Frequency is the speed of the oscillation and is measured in Hertz. Phase is the measure of displacement between two similar features of waveforms. Thanks to frequency modulation, a large volume of information can be sent in just a short period and with good security features.


Radio Stations


Radio hosts produce sound through their own voices. These sound waves are picked up by the microphones which turn them into electrical signals. These signals are modulated and transmitted by the broadcasting towers. They need to be transmitted at the assigned FM or AM frequency to prevent interference. Nearby radio sets in households pick up the signal if they are tuned to the channel. The receiver then unpacks the information contained which is the electrical signal fed to the speakers. These speakers reproduce the voices of the radio hosts so that people can listen in.


Handheld Radios


The earliest radio models were big, heavy and bulky. Improvements in technology such as the advent of semiconductors led to their miniaturization. Some are now as small as a pack of cards. Aside from those meant to receive commercial broadcasts, there are also handheld radios that are meant for two-way communications. These are often used by the military in combat operations and construction managers in large sites. Anything that requires coordination over a large area where direct line of sight is not possible can depend on these devices. More than two people can talk this way such that different units can act as one. The only thing needed is for them to tune in to the same frequency.


Remote-controlled Toys


Aside from voice communication, radio technology is also used in applications that require the continuous transmission of electronic commands. The best example would be remote-controlled cars. The controllers have a transmitter that sends out signals based on how you want the toy to move. Each car units have a receiver that picks up the signals and decodes the commands. They interface with the circuit that connects to the electric motors. These then tell the wheels to move forward, backward, turn left, or turn right.