intermediate frequency filter

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• Intermediate frequency — In communications and electronic engineering, an intermediate frequency (IF) is a frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception. The intermediate frequency is created by mixing the carrier… …   Wikipedia

• Mechanical filter — Figure 1. A mechanical filter made by the Kokusai Electric Company intended for selecting the narrow 2 kHz bandwidth signals in SSB radio receivers. It operates at 455 kHz, a common IF for these receivers, and is dimensioned 45×15×15 mm ( …   Wikipedia

• Crystal filter — A crystal filter is a special form of quartz crystal used in electronics systems, in particular communications devices. It provides a very precisely defined centre frequency and very steep bandpass characteristics, that is a very high Q factor… …   Wikipedia

• Nyquist filter — A Nyquist filter is an electronic filter used in TV receivers to equalize the video characteristics. The filter is named after the Swedish–US engineer Harry Nyquist (1889–1976). Contents 1 VSB 2 Example of a VSB 3 Demodulation problems …   Wikipedia

• Beat frequency oscillator — A beat frequency oscillator or BFO in radio telegraphy, is a dedicated oscillator used to create an audio frequency signal from carrier wave transmissions to make them audible, as they are not broadcast as such. The signal from the BFO is then… …   Wikipedia

• Tuned radio frequency receiver — A tuned radio frequency receiver (TRF receiver) is a radio receiver that is usually composed of several tuned radio frequency amplifiers followed by circuits to detect and amplify the audio signal. A 3 stage TRF receiver includes a RF stage, a… …   Wikipedia

• Image frequency — Image frequency: In radio reception using heterodyning in the tuning process, an undesired input frequency that is capable of producing the same intermediate frequency (IF) that the desired input frequency produces. In a heterodyne receiver… …   Wikipedia

• Roofing filter — A roofing filter is a type of filter used in a HF receiver (shortwave radio). It is usually found after the first receiver mixer. The goal of a roofing filter is to reduce the passband of the 1st intermediate frequency (IF) to about 6 20 kHz, so… …   Wikipedia

• Anti-aliasing filter — An anti aliasing filter is a filter used before a signal sampler, to restrict the bandwidth of a signal to approximately satisfy the sampling theorem. Since the theorem states that unambiguous interpretation of the signal from its samples is… …   Wikipedia

• Superheterodyne receiver — A 5 tube superheterodyne receiver made in Japan around 1955 In electronics, a superheterodyne receiver (sometimes shortened to superhet) uses frequency mixing or heterodyning to convert a received signal to a fixed intermediate frequency, which… …   Wikipedia

• Satellite modem — A satellite modem or sat modem is a modem used to establish data transfers using a communications satellite as a relay.There is a wide range of satellite modems from cheap devices for home internet access to expensive multifunctional equipment… …   Wikipedia