Operatinal amplifier Operatinal amplifier or OPAMP are basic element in an analogue circuit. Opamp is a linear device. When signal is applied to minus terminal of opamp then output is in opposite phase of input. Differential gain of opamp should be greater than common mode gain. Ideal value of common mode rejection ratio CMMR is …
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Feedback amplifier Feedback factor varies with frequency, so negative feedback may change to positive and vice versa. OPAMP comparator doesn’t have any feedback. In common emitter amplifier the unbypassed emitter resistance is current series feedback. Voltage negative feedback is used in emitter follower. De-sensitivity factor is defined as the factor with which the feedback desensitizes …
Simplest sinusoidal variable frequency oscillator is amstrong circuit. Simplest sinusoidal constant frequency oscillator is crystal oscillator. Parasitic oscillation is caused by transistor inter electrode capacitance. If you movie towards an oscillating circuit its frequency increases because of hand capacitance. Frequency stability is maximum in wein bridge oscillator. Practically in order to change frequency of oscillation …
Antennas are inductive.Microwave antennas are horn antenna, Parabolic antenna, slot antenna, dipole antenna, dielectric antenna, printed antenna, phase array antenna, Micro strip patch antenna, Plasma antenna, MIMO antenna. Horn antenna is the most widely used microwave antenna. As frequency increases gain of horn antenna also increases. Horn antenna is a fixed size antenna. Horn antenna …
Most of the link uses 4 and 6 GHz. Short term fading in microwave communication links can be overcome by diversity reception and transmission.Ionosphere propagation is not possible in micro wave communication because it penetrate through ionosphere. In microwave communication links, the rain drop attenuation experienced is mainly due to absorption of microwave energy by …