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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Q. A CB amplifier has IE = 3.5 mA, a = 0.98 and RL = 600 Ω. The input impedance

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Q. An amplifier has open loop gain of 100, input impedance 1 kΩ and output impedance 100 Ω. If negative feedback with β = 0.99 is used, the new input and output impedances are

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Q. In a BJT amplifier the power gain from base to collector is 4000. The power gain in dB is

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

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Q. A buffer amplifier should have

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Q. If the differential voltage gain and the common mode voltage gain of a differential amplifier are 48 dB and 2 dB respectively, then its common mode rejection ratio is

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Q. An npn transistor has a Beta cutoff frequency fβ of 1 MHz, and a common emitter short circuit low frequency current gain β0 of 200. It unity gain frequency fT and the alpha cut off frequency fa2 respectively are

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Q. If input frequency is 50 Hz, the frequency of output wave in a full wave diode rectifier circuit is

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Q. A class A transformer coupled power amplifier is to deliver 10 W output. The power rating of transistor should not be less than

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Q. A half wave diode rectifier uses a diode having forward resistance of 50 ohms. The load resistance is also 50 ohms. Then the voltage regulation is

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Q. A Hartley oscillator is used for

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Q. In Class C operation the collector current looks like

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