Carrier is generated by high precision, temperature controlled crystal oscillator, operates at a frequency 124 KHz. Output of this master oscillator is feed to harmonic generator, which supplies super group carrier frequencies. Required harmonics are selected by filters. 124 KHz frequency is subdivided into 4 KHz. This 4 KHz is then used in odd and …
Audio power amplifiers Power amplifiers handles large signals (not very large). Size of power transistor is large, to dissipate heat. Tuned amplifier is used in RF application. Class A power amplifier uses one transistor, this transistor never turn off which is its main disadvantage. Driver stage commonly uses class A. Class A amplifier is most …
Emitter is moderate size and heavily doped. Collector is large in size and moderately doped. Base is thin and lightly doped. When collector supply is 5V then collector cut off voltage is 5V. Zero signal condition is when transistor see dc load. Cut-off region – both junctions are reverse biased, Saturation region – both junctions …
Semiconductor diode Ideal diode conduct current in only one direction. Forward resistance of ideal diode is zero. Reverse bias resistance value is infinity. Barrier potential is generated by diffusion of electrons. PN diode can be made by alloying technique, diffusion technique, vapour deposition technique (epitaxial growth), rate growth technique Thickness of depletion region is 1 …
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Insulator has negative temperature coefficient. Intrinsic Semiconductor has negative temperature coefficient. Extrinsic Semiconductor has positive temperature coefficient. Metal has positive temperature coefficient. Resistance of semiconductor decreases exponentially in case of insulator it is linearly decreasing. In metal forbidden band gap Eg between conduction and valance band is zero, i.e, two bands are overlapped Band gap …
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