Q. In a class C power amplifier the input frequency of ac signal is 1 MHz. If tank circuit has C = 1000 pF, the value of L =

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Q. In calculating output impedance of an amplifier the source is replaced by an open circuit.

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Q. For transistor 2 N 338 the manufacturer specifies Pmax = 100 mW at 250°C free air temperature and maximum junction temperature of 125°C. Its thermal resistance is

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Q. A 120 V, 30 Hz source feeds a half wave rectifier circuit through a 4 : 1 step down transformer, the average output voltage is

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Q. The slew rate of an ideal op-amp is

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Q. Regulation of the DC power supply of 12 V, 100 mA is the effective resistance of power supply is 20 Ω

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Q. Assertion (A): An op-amp has high voltage gain, high input impedance and low output impedance

Reason (R): Negative feedback increases output impedance

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Q. A transistor has a maximum power dissipation of 350 mW at an ambient temperature of 25°C. If derating factor is 2 mW/°C, the maximum power dissipation for 40°C ambient temperature is

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Q. The output voltage waveform of a CE amplifier is fed to a dc coupled CRO. The trace on the screen will be

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Q. In an RC phase shift oscillator, the total phase shift of the three RC lead networks is

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Q. It has been found that in a rectifier circuit with RC filter one RC section reduces ripple by 15%. Two RC sections are used in cascade the reduction in ripple would be

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Q. An op-amp has

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Q. As the ratio Rf/RL increases the efficiency of a rectifier increases.

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Q. If the Q of a single stage single tuned amplifier is doubled, the bandwidth will

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Q. In full wave rectification, if the input frequency is 50 Hz, then frequency at the output of filter is

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Q. The turn ratio of a transformer is 20:1, if a load of 10Ω is connected across the secondary, what will be the effective resistance seen looking into the Primary?

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Q. In a CE amplifier circuit the ac voltage between emitter and ground

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Q. A CE amplifier has re = 6 Ω, β = 100 and a = 0.98. The input impedance is

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Q. A full wave diode rectifier using centre tapped transformer has diodes with forward resistance of 50 ohms each. The load resistance of 50 ohms each. The load resistance is also 50 ohms. The voltage regulation is

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Q. Leakage current approximately doubles for every 10°C increase in the temperature of a transistor has ICBO = 400 nA at 25°C, then its leakage current at 80°C

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