Television Reception

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Block diagram of a conventional FSTV receiver.
A television (TV) receiver has a tunable front end, an oscillator and mixer, a set of IF amplifiers, a video demodulator, an audio demodulator and amplifier chain, a picture CRT or display with associated peripheral circuitry, and a loudspeaker.

Fast-Scan TV

Above figure is a block diagram of a receiver for conventional analog FSTV. In the United States, conventional FSTV broadcasts are made on 68 different channels numbered from 2 through 69. Each channel is 6 MHz wide, including video and audio information. Channels 2 through 13 comprise the VHF TV broadcast channels. Channels 14 through 69 are the UHF TV broadcast channels. In digital cable television, there are more channels. The number of possible channels is virtually unlimited, because signals are not transmitted over the air and do not consume EM spectrum space.

Slow-Scan TV

A slow-scan television (SSTV) communications station needs a transceiver with SSB capability, a standard TV set or personal computer, a video camera, and a scan converter that translates between the SSTV signal and either FSTV imagery or computer video data. The scan converter consists of two data converters (one for receiving and the other for transmitting), some digital memory, a tone generator, and a TV detector. Scan converters are commercially available. Computers can be programmed to perform this function. Some amateur radio operators build their own scan converters.