Inelectronics andradio, atuner is a type ofreceiver subsystem that receivesRF transmissions, such asAM orFM broadcasts, and converts the selectedcarrier frequency into a form suitable for further processing or output, such as to anamplifier orloudspeaker. A tuner is also a standalonehome audio product,component, ordevice called anAM/FM tuner or astereo tuner that is part of ahi-fi or stereo system, or aTV tuner for television broadcasts. The verbtuning in radio contexts means adjusting the receiver to detect the desired radio signal carrier frequency that a particular radio station uses. Tuners were a majorconsumer electronics product in the 20th century but in practice are often integrated into other products in the modern day, such asstereo or AV receivers orportable radios.

The purpose of a tuner's design is to reduce noise and have a strong ability to amplify the wanted signal.^[3] Tuners may bemonophonic orstereophonic, and generally output left and right channels of sound.^[4] Tuners generally include a tuning knob or keypad to adjust thefrequency, i.e. the intended radio station, measured inmegahertz (e.g. 101.1 MHz). Mistuning is the greatest source of distortion in FM reception.^[3] Some models realize manual tuning by means of mechanically operated gangedvariable capacitors (gangs). Often several sections are provided on a tuning capacitor, to tune several stages of the receiver in tandem, or to allow switching between different frequency bands. A later method used apotentiometer supplying a variable voltage tovaractor diodes in the local oscillator and tank circuits of front end tuner, for electronic tuning. Modern radio tuners use asuperheterodyne receiver with tuning selected by adjustment of the frequency of a local oscillator. This system shifts the radio frequency of interest to a fixed frequency so that it can be tuned with fixed-frequencyband-pass filter. Still later,phase locked loop methods were used, withmicroprocessor control.^{[citation needed]}

Thecrystal radio receiver is the simplest kind of radio receiver or tuner, and was the basis for the first commercially successful type of radio product design. Inexpensive and reliable, it was sold in millions of units and became popular in kits used by hobbyists, and was a major factor in the popularity ofradio broadcasting around 1920.^[5][6] The crystal radio consists of anantenna, a variableinductor and a variable capacitor connected in parallel. This creates atank circuit which responds to oneresonant frequency when combined with adetector, also known as ademodulator (diode D1 in the circuit).^[7][6] Stereophonic receivers include adecoder as well.^[8]

Vacuum tubes made crystal sets obsolete in the 1920s due to their effective amplification.^[10] From the 1920s until the 1960s, most tuners used avacuum tube-based design. Manufacturing shifted tosolid state electronics in the 1960s, but this didn't always result in improved sound quality compared to the older tube tuners.^[11][12] Theradiogram, which combined agramophone with a radio, was a predecessor of the hi-fi tuner.^[13]

Thetransistor was invented in 1947 and largely replaced tubes.^[14] TheMOSFET was used because it is capable of handling larger inputs thanbipolar transistors.^[8] Starting in the 1960s, Japanesetransistor radios, which were cheaper despite their crudeness compared to American designs, began to outcompete the American products in the portable radio market. Eventually, after switching from germanium to silicon transistors, the Japanese consumer electronics companies achieved a dominant market position.Heathkit, an American company which had supplied popular kits for electronic devices since the 1940s, went out of business in 1980.^[14][15]

FM broadcasting originated in the United States and was adopted as a worldwide standard.^[16] FM broadcasting in stereo in the USA began in 1961 when authorized by theFCC. This led to greater demand for new radio stations and better technology in radios. The growth of hi-fi stereo systems andcar radios in turn led to a boost in FM listening. FM surpassed AM radio in 1978.^[17] FM also doubled the number of stations, enabling specialized broadcasts for different genres of music. It also required consumers to purchase new equipment.^[13] The broadcast audio FM band (88 – 108 MHz in most countries) is around100 times higher in frequency than the AM band and provides enough space for a bandwidth of50 kHz. This bandwidth is sufficient to transmit both stereo channels with almost the fullhearing range.^{[citation needed]}

ThePost–World War II economic expansion in the US led to the growth of hi-fi products, increasingly seen ashigh techhardware, with requisitejargon, and separated into premium quality components with high-class aesthetics and marketing.^[20] The 1970s and 80s were the peak period for the hi-fi audio market.^[11] Demand increased for stereo products which fueled the growth of the industry as Japan caught up with the US.^[21] Standalone audio stereo FM tuners are still sought after foraudiophile andTV/FM DX applications, especially those produced in the 1970s and early 1980s, when performance and manufacturing standards were higher.^[22] TheMcIntosh MR78 (1972) is known as one of the first FM tuners precise enough to tune into a weaker station broadcast on the same frequency as another stronger signal.^[23]

As a result of circuitminiaturization, tuners began to be integrated with other products such asamplifiers andpreamps, and otherdigital electronics, and marketed asAV or stereo receivers forhome theater or hi-fi systems.^[24][25] The Japanese development of silicon transistor technology led to popular radio products in the 1980s such as theboombox and theSony Walkman.^[13] Although integrated hi-fi stereo systems and AV or stereo receivers contain integrated tuners, separate components are sometimes preferred for higher quality.^[26][27] Separating amplification also often increases overall performance.^[28]

A television tuner or TV tuner, also called a TV receiver, is a component or subsystem that convertsanalog television ordigital television transmissions intoaudio and video signals which can be further processed to produce sound and apicture.^[29][30][31] A TV tuner must filter out unwanted signals and have a high signal-to-noise ratio.^[32] Television standards supported by TV tuners includePAL,NTSC,SECAM,ATSC,DVB-C,DVB-T,DVB-T2,ISDB,DTMB,T-DMB, and open cable.VHF/UHF TV tuners are rarely found as a separate component, but are incorporated intotelevision sets.Cable boxes,converter boxes and otherset top boxes contain tuners for digital TV services, and send their output viaSCART or other connector, or using anRF modulator (typically onchannel 36 in Europe andchannel 3/4 in North America) to TV receivers that do not natively support the services. They provide outputs viacomposite,S-video, orcomponent video. Many can be used withvideo monitors that do not have a TV tuner or direct video input. They are often part of aVCR ordigital video recorder (DVR, PVR).^{[citation needed]}

Analog tuners can tune onlyanalog signals. AnATSC tuner is a digital tuner that tunesdigital signals only. Some digital tuners provide an analog bypass. An example frequency range is48.25 MHz – 855.25 MHz(E2-E69), with a tuning frequency step size of31.25, 50 or 62.5 kHz. Before the use of solid-state frequency synthesizers, covering the broad range of TV signal frequencies with a single tuned circuit and sufficient precision was uneconomic.Television channel frequencies were non-contiguous, with many non-broadcast services interleaved between VHF channels 6 and 7 in North America, for example. Instead, TV tuners of the era incorporated multiple sets of tuned circuits for the main signal path andlocal oscillator circuit. These "turret" tuners mechanically switched the receiving circuits by rotating a knob to select the desired channel. Channels were presented in fixed sequence, with no means to skip channels unused in a particular area. When UHF TV broadcasting was made available, often two complete separate tuner stages were used, with separate tuning knobs for selection of VHF band and UHF band channels. To allow for a small amount of drift or misalignment of the tuner with the actual transmitted frequency, tuners of that era included a "fine tuning" knob to allow minor adjustment for best reception. The combination of high frequencies, multiple electrical contacts, and frequent changing of channels in the tuner made it a high maintenance part of the television receiver, as relatively small electrical or mechanical problems with the tuner would make the set unusable.^{[citation needed]}

Computers may use an internalTV tuner card orUSB connected external tuner to allow reception of overt-the-air broadcasts or cable signals.^{[citation needed]}

Wikimedia Commons has media related toHi-Fi tuners.

• Minimum detectable signal
• Radio scanner

• Receiver (radio)
• Set-top box
• Wireless tuning and filtering
• Radio electronics
• Consumer electronics
• Sound
• Audio engineering
• Audio players

• Articles with short description
• Short description matches Wikidata
• All articles with unsourced statements
• Articles with unsourced statements from October 2024
• Articles with unsourced statements from November 2024
• Commons category link is locally defined