TV tuner card

A TV tuner card is a computer component that allows television signals to be received by a computer. Most TV tuners also function as video capture cards, allowing them to record television programs onto a hard disk.TV tuners are available as PCI-bus expansion card, PCIe (PCI Express) bus or USB devices. The trend is towards USB devices. In addition, some video cards double as TV tuners, notably the ATI All-In-Wonder series. The card contains a receiver, tuner, demodulator, and an analog-to-digital converter for analog TV. Many cards are limited to the radio frequencies and video formats used in the country of sale. However, many TV tuners used in computers use DSP, so a firmware upgrade is often all that's necessary to change the supported video format. Many newer TV tuners have flash memory big enough to hold the firmwares for decoding several different video formats, making it possible to use the tuner in many countries without having to flash the firmware. In addition to the frequency tuner, many include a composite video input. Many TV tuners can function as FM radios: this is because the FM radio spectrum lies between television channels 6 and 7, and the DSP can be easily programmed to decode FM.
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