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Electronic Circuits and Devices1ELECTRONIC CIRCUITS AND DEVICESBy NameCourseInstructorInstitutionLocationDate
Electronic Circuits and Devices2Types of Amplifiers and their PerformancesAn amplifier is a device that is used in increasing the amplitude of a signal without makingalterations to the other parameters of the waveforms including the wave shape or the frequency.Amplifiers are very commonly used in circuits in various electronics and are used to carry outvarious functions in numerous electronic systems[CITATION Tre15 \p 189 \l 1033 ]. In an amplifiersignal, the details of the type ofamplifier are not provided and instead only the direction of flowof the signals is illustrated and is normally assumed to be in the left to direct direction.Audio Frequency AmplifiersThese are amplifier mainly used in the amplification of signals in the hearing range of humansthat is about 20Hz to 20 kHz. This range is extended even further by some Hi-Fi audio amplifiersthat go as high as 100 kHz. On the other hand, there are other types of audio amplifiers that arecapable of restricting the limit if the high frequency to 15 kHz or even lower.
Electronic Circuits and Devices3The amplification of low levels of signals from disk pickups and microphones is done with theaid of intermediate frequency amplifiers. Amplifiers are also able to perform functions such asmixing of various inputs, correction of tones as well as equalization of signal levels by extracircuitry. Amplifiers have a medium to high output of resistance and high voltage gain. Suchamplifiers are used in receiving the amplified input for a range of voltage amplifiers andthereafter provide enough power to operate loudspeakers.Intermediate Frequency AmplifiersThese are tuned amplifiers that are applied in radio devices, radar devices as well as in televisionsets and they are mainly used in providing the majority of the amplification of voltage of atelevision or radar signals immediately just before the separation or demodulation of the audio orvideo information carried by signals from the radio signal. These amplifiers work at frequenciesthat are lower than the frequencies of the radio wave that are received but are higher than thevideo or audio signals that are finally produced by the system[CITATION Cat111 \p 188 \l 1033 ].The equipment typedetermines the bandwidth of these amplifiers. The operation frequency ofAM receivers and I.F amplifiers is about 470 kHz with a bandwidth of 10 kHz.
Electronic Circuits and Devices4RF amplifiersThese are tuned amplifiers that have the operation frequency being controlled by tuned circuitequipment. The circuit equipment may or may not be adjustable and this depends on the role ofthe amplifier[CITATION Ear11 \p 312 \l 1033 ]. The bandwidth is as well a factor of the purpose ofthe device and could be relatively narrow or wide. RF amplifiers have relatively low amplifierinput resistance. Some of these amplifiers have little or absolutely no gain at all and instead actas primary buffer between an antenna used for receiving signals and thereafter circuit and thuspreventing any unwanted signals of high levels to the antenna port to the receiver circuits. Suchhigh level unwanted signals may be re-transmitted as interface.RF amplifierRF amplifiers are mostly applied in the earliest stages of a receiver and have low levels of noiseperformance. The noise mainly comes from the background sources which result from theoperations of any electronic device which is to be kept a minimum by the amplifier as it will be