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Frequency modulation

Index Frequency modulation

In telecommunications and signal processing, frequency modulation (FM) is the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. [1]

101 relations: Adjacent channel, Amateur radio, Amplitude, Amplitude modulation, Analog signal, Angle modulation, Audio frequency, Bandwidth (signal processing), Baseband, BBC, Bessel function, Binary number, Broadcasting, Capture effect, Carrier frequency, Carrier wave, Chirp, Chirp spread spectrum, Chrominance, Class-D amplifier, Constant envelope, Continuous wave, Continuous-wave radar, Crystal oscillator, Decibel, Detector (radio), Digital data, Drift (telecommunication), Dynamic range compression, Edwin Howard Armstrong, Electroencephalography, Electromagnetic interference, Equalization (audio), Family Radio Service, Fax modem, FM broadcast band, FM broadcasting, FM-UWB, Foster–Seeley discriminator, Fourier analysis, Frequency deviation, Frequency drift, Frequency modulation synthesis, Frequency multiplier, Frequency-shift keying, Harmonic, Hertz, High fidelity, History of radio, Infant, ..., Information, Instantaneous phase, Institute of Radio Engineers, Interference (communication), Intermediate frequency, Linear amplifier, Low-power electronics, Luma (video), Magnetic tape, Mikhail Aleksandrovich Bonch-Bruevich, Modem, Modulation, Morse code, Multiplexing, Nizhny Novgorod Radio Laboratory, Noise (radio), Noise reduction, Personal computer, Phase modulation, Phase-locked loop, Pre-echo, Print-through, Quadrature amplitude modulation, Radar, Radio, Radio broadcasting, Radio frequency, Radio receiver, Radioteletype, Rule of thumb, Selectivity (electronic), Sideband, Signal processing, Signal-to-noise ratio, Sine wave, Sound card, Spectral density, Speech, Stereophonic sound, Synthesizer, Tape bias, Telecommunication, Telemetry, Time base correction, Tuner (radio), Two-way radio, Very high frequency, VHS, Video 2000, Videocassette recorder, Voltage-controlled oscillator. Expand index (51 more) »

Adjacent channel

In broadcasting an adjacent channel is an AM, FM, or TV channel that is next to another channel.

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Amateur radio

Amateur radio, also known as ham radio, describes the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communication.

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The amplitude of a periodic variable is a measure of its change over a single period (such as time or spatial period).

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Amplitude modulation

Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting information via a radio carrier wave.

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Analog signal

An analog signal is any continuous signal for which the time varying feature (variable) of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal.

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Angle modulation

Angle modulation is a class of carrier modulation that is used in telecommunications transmission systems.

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Audio frequency

An audio frequency (abbreviation: AF) or audible frequency is characterized as a periodic vibration whose frequency is audible to the average human.

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Bandwidth (signal processing)

Bandwidth is the difference between the upper and lower frequencies in a continuous band of frequencies.

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Baseband is a signal that has a very narrow and near-zero frequency range, i.e. a spectral magnitude that is nonzero only for frequencies in the vicinity of the origin (termed f.

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The British Broadcasting Corporation (BBC) is a British public service broadcaster.

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Bessel function

Bessel functions, first defined by the mathematician Daniel Bernoulli and then generalized by Friedrich Bessel, are the canonical solutions of Bessel's differential equation for an arbitrary complex number, the order of the Bessel function.

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Binary number

In mathematics and digital electronics, a binary number is a number expressed in the base-2 numeral system or binary numeral system, which uses only two symbols: typically 0 (zero) and 1 (one).

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Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model.

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Capture effect

In telecommunications, the capture effect, or FM capture effect, is a phenomenon associated with FM reception in which only the stronger of two signals at, or near, the same frequency or channel will be demodulated.

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Carrier frequency

In telecommunication systems, Carrier frequency is a technical term used to indicate.

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Carrier wave

In telecommunications, a carrier wave, carrier signal, or just carrier, is a waveform (usually sinusoidal) that is modulated (modified) with an input signal for the purpose of conveying information.

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A chirp is a signal in which the frequency increases (up-chirp) or decreases (down-chirp) with time.

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Chirp spread spectrum

In digital communications, chirp spread spectrum (CSS) is a spread spectrum technique that uses wideband linear frequency modulated chirp pulses to encode information.

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Chrominance (chroma or C for short) is the signal used in video systems to convey the color information of the picture, separately from the accompanying luma signal (or Y for short).

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Class-D amplifier

A class-D amplifier or switching amplifier is an electronic amplifier in which the amplifying devices (transistors, usually MOSFETs) operate as electronic switches, and not as linear gain devices as in other amplifiers.

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Constant envelope

Constant envelope is achieved when a sinusoidal waveform reaches equilibrium in a specific system.

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Continuous wave

A continuous wave or continuous waveform (CW) is an electromagnetic wave of constant amplitude and frequency, almost always a sine wave, that for mathematical analysis is considered to be of infinite duration.

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Continuous-wave radar

Continuous-wave radar is a type of radar system where a known stable frequency continuous wave radio energy is transmitted and then received from any reflecting objects.

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Crystal oscillator

A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a precise frequency.

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The decibel (symbol: dB) is a unit of measurement used to express the ratio of one value of a physical property to another on a logarithmic scale.

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Detector (radio)

In radio, a detector is a device or circuit that extracts information from a modulated radio frequency current or voltage.

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Digital data

Digital data, in information theory and information systems, is the discrete, discontinuous representation of information or works.

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Drift (telecommunication)

In telecommunication, a drift is a comparatively long-term change in an attribute, value, or operational parameter of a system or equipment.

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Dynamic range compression

Dynamic range compression (DRC) or simply compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds thus reducing or compressing an audio signal's dynamic range.

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Edwin Howard Armstrong

Edwin Howard Armstrong (December 18, 1890 – February 1, 1954) was an American electrical engineer and inventor, best known for developing FM (frequency modulation) radio and the superheterodyne receiver system.

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Electroencephalography (EEG) is an electrophysiological monitoring method to record electrical activity of the brain.

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Electromagnetic interference

Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.

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Equalization (audio)

Equalization or equalisation is the process of adjusting the balance between frequency components within an electronic signal.

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Family Radio Service

The Family Radio Service (FRS) is an improved walkie-talkie radio system authorized in the United States since 1996.

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Fax modem

A fax modem enables a computer to transmit and receive documents as faxes on a telephone line.

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FM broadcast band

The FM broadcast band, used for FM broadcast radio by radio stations, differs between different parts of the world.

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FM broadcasting

FM broadcasting is a method of radio broadcasting using frequency modulation (FM) technology.

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FM-UWB is a modulation scheme using double FM: low-modulation index digital FSK followed by high-modulation index analog FM to create a constant envelope UWB signal.

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Foster–Seeley discriminator

The Foster–Seeley discriminator is a common type of FM detector circuit, invented in 1936 by Dudley E. Foster and Stuart William Seeley.

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Fourier analysis

In mathematics, Fourier analysis is the study of the way general functions may be represented or approximated by sums of simpler trigonometric functions.

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Frequency deviation

Frequency deviation (f_) is used in FM radio to describe the maximum difference between an FM modulated frequency and the nominal carrier frequency.

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Frequency drift

In electrical engineering, and particularly in telecommunications, frequency drift is an unintended and generally arbitrary offset of an oscillator from its nominal frequency.

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Frequency modulation synthesis

Frequency modulation synthesis (or FM synthesis) is a form of sound synthesis where the timbre of a simple waveform (such as a square, triangle, or sawtooth) called the carrier, is changed by modulating its frequency with a modulator frequency that is also in the same or similar audio range, so that a more complex timbre results.

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Frequency multiplier

In electronics, a frequency multiplier is an electronic circuit that generates an output signal whose output frequency is a harmonic (multiple) of its input frequency.

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Frequency-shift keying

Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier signal.

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A harmonic is any member of the harmonic series, a divergent infinite series.

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The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.

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High fidelity

High fidelity (often shortened to hi-fi or hifi) is a term used by listeners, audiophiles and home audio enthusiasts to refer to high-quality reproduction of sound.

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History of radio

The early history of radio is the history of technology that produces and uses radio instruments that use radio waves.

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An infant (from the Latin word infans, meaning "unable to speak" or "speechless") is the more formal or specialised synonym for "baby", the very young offspring of a human.

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Information is any entity or form that provides the answer to a question of some kind or resolves uncertainty.

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Instantaneous phase

Instantaneous phase and instantaneous frequency are important concepts in signal processing that occur in the context of the representation and analysis of time-varying functions.

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Institute of Radio Engineers

The Institute of Radio Engineers (IRE) was a professional organization which existed from 1912 until December 31, 1962.

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Interference (communication)

In communications and electronics, especially in telecommunications, interference is anything which modifies, or disrupts a signal as it travels along a channel between a source and a receiver.

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Intermediate frequency

In communications and electronic engineering, an intermediate frequency (IF) is a frequency to which a carrier wave is shifted as an intermediate step in transmission or reception.

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Linear amplifier

A linear amplifier is an electronic circuit whose output is proportional to its input, but capable of delivering more power into a load.

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Low-power electronics

Low-power electronics are electronics, such as notebook processors, that have been designed to use less electric power.

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Luma (video)

In video, luma represents the brightness in an image (the "black-and-white" or achromatic portion of the image).

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Magnetic tape

Magnetic tape is a medium for magnetic recording, made of a thin, magnetizable coating on a long, narrow strip of plastic film.

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Mikhail Aleksandrovich Bonch-Bruevich

Mikhail Aleksandrovich Bonch-Bruevich (a, 22 February 1888 – 7 March 1940), sometimes spelled Bonch-Bruyevich, was a Russian engineer, scientist, and professor.

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A modem (modulator–demodulator) is a network hardware device that modulates one or more carrier wave signals to encode digital information for transmission and demodulates signals to decode the transmitted information.

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In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted.

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Morse code

Morse code is a method of transmitting text information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment.

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In telecommunications and computer networks, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium.

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Nizhny Novgorod Radio Laboratory

Nizhny Novgorod Radio Laboratory (Нижегородская радиолаборатория, НРЛ) was the first Soviet science laboratory in the field of radio electronics.

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Noise (radio)

In radio reception, noise is the superposition of white noise and other disturbing influences on the signal, caused either by thermal noise and other electronic noise from receiver input circuits or by interference from radiated electromagnetic noise picked up by the receiver's antenna.

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Noise reduction

Noise reduction is the process of removing noise from a signal.

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Personal computer

A personal computer (PC) is a multi-purpose computer whose size, capabilities, and price make it feasible for individual use.

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Phase modulation

Phase modulation (PM) is a modulation pattern for conditioning communication signals for transmission.

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Phase-locked loop

A phase-locked loop or phase lock loop abbreviated as PLL is a control system that generates an output signal whose phase is related to the phase of an input signal.

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Pre-echo, sometimes called a forward echo, (not to be confused with reverse echo) is a digital audio compression artifact where a sound is heard before it occurs (hence the name).

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Print-through (sometimes referred to as bleed-through) is a generally undesirable effect that arises in the use of magnetic tape for storing analogue information, in particular music.

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Quadrature amplitude modulation

Quadrature amplitude modulation (QAM) is the name of a family of digital modulation methods and a related family of analog modulation methods widely used in modern telecommunications to transmit information.

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Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects.

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Radio is the technology of using radio waves to carry information, such as sound, by systematically modulating properties of electromagnetic energy waves transmitted through space, such as their amplitude, frequency, phase, or pulse width.

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Radio broadcasting

Radio broadcasting is transmission by radio waves intended to reach a wide audience.

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Radio frequency

Radio frequency (RF) refers to oscillatory change in voltage or current in a circuit, waveguide or transmission line in the range extending from around twenty thousand times per second to around three hundred billion times per second, roughly between the upper limit of audio and the lower limit of infrared.

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Radio receiver

In radio communications, a radio receiver (receiver or simply radio) is an electronic device that receives radio waves and converts the information carried by them to a usable form.

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Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link.

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Rule of thumb

The English phrase rule of thumb refers to a principle with broad application that is not intended to be strictly accurate or reliable for every situation.

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Selectivity (electronic)

Selectivity is a measure of the performance of a radio receiver to respond only to the radio signal it is tuned to (such as a radio station) and reject other signals nearby in frequency, such as another broadcast on an adjacent channel.

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In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing power as a result of the modulation process.

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Signal processing

Signal processing concerns the analysis, synthesis, and modification of signals, which are broadly defined as functions conveying "information about the behavior or attributes of some phenomenon", such as sound, images, and biological measurements.

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Signal-to-noise ratio

Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.

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Sine wave

A sine wave or sinusoid is a mathematical curve that describes a smooth periodic oscillation.

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Sound card

A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under control of computer programs.

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Spectral density

The power spectrum S_(f) of a time series x(t) describes the distribution of power into frequency components composing that signal.

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Speech is the vocalized form of communication used by humans and some animals, which is based upon the syntactic combination of items drawn from the lexicon.

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Stereophonic sound

Stereophonic sound or, more commonly, stereo, is a method of sound reproduction that creates an illusion of multi-directional audible perspective.

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A synthesizer (often abbreviated as synth, also spelled synthesiser) is an electronic musical instrument that generates electric signals that are converted to sound through instrument amplifiers and loudspeakers or headphones.

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Tape bias

Tape bias is the term for two techniques, AC bias and DC bias, that improve the fidelity of analogue tape recorders.

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Telecommunication is the transmission of signs, signals, messages, words, writings, images and sounds or information of any nature by wire, radio, optical or other electromagnetic systems.

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Telemetry is an automated communications process by which measurements and other data are collected at remote or inaccessible points and transmitted to receiving equipment for monitoring.

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Time base correction

Time base correction is a technique to reduce or eliminate errors caused by mechanical instability present in analog recordings on mechanical media.

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Tuner (radio)

A tuner is a subsystem that receives radio frequency (RF) transmissions like radio broadcasts and converts the selected carrier frequency and its associated bandwidth into a fixed frequency that is suitable for further processing, usually because a lower frequency is used on the output.

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Two-way radio

A two-way radio is a radio that can do both transmit and receive a signal (a transceiver), unlike a broadcast receiver which only receives content.

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Very high frequency

Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten to one meter.

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The Video Home System (VHS) is a standard for consumer-level analog video recording on tape cassettes.

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Video 2000

Video 2000 (also known as V2000, with the tape standard Video Compact Cassette, or VCC) is a consumer videocassette system and analogue recording standard developed by Philips and Grundig to compete with JVC's VHS and Sony's Betamax video technologies.

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Videocassette recorder

A videocassette recorder, VCR, or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the recording.

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Voltage-controlled oscillator

A microwave (12–18nbspGHz) voltage-controlled oscillator A voltage-controlled oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input.

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Redirects here:

Analog FM, Analog frequency modulation, F M, F.m., FM (modulation), Frequency Modulation, Frequency modulated, Frequency modulator, Frequency-modulated, Frequency-modulation, NFM, Narrowband FM, Wideband FM.


[1] https://en.wikipedia.org/wiki/Frequency_modulation

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