The power input to a power amplifier is _____ quantity.
Aac
Bpulsating dc
Cdc
Dsinusoidal
#242📘 reviewer_appEasy
When shock-excited, a crystal will produce alternating emf longer than an LC circuit because crystal
Ahas greater mechanical strength
Bhas fewer losses
Cis small-sized
Dis very rigid
#243📘 reviewer_appEasy
The stability of a regulated power supply is equivalent to
Achange of output voltage over the change in supply voltage
Bchange in supply voltage over the change of output voltage
Cproduct of the output voltage and the supply voltage
Dthe difference of an output voltage to its supply voltage
#244📘 reviewer_appEasy
An oscillator circuit that uses a tapped coil in the tuned circuit is called
AHartley
BColpitts
Ccrystal
Dpierce
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Which of the following is not a FET amplifier configuration
Acommon base amplifier
Bcommon drain amplifier
Ccommon source amplifier
Dcommon gate amplifier
#246📘 reviewer_appEasy
The number of transistor in a single stage amplifier is
A2
B3
C1
D4
#247📘 reviewer_appMedium
Series current negative feedback occurs when the feedback voltage is proportional to the
Aoutput voltage
Boutput impedance
Coutput current
Doutput power
#248📘 reviewer_appEasy
Which of the following is NOT an oscillator requirement?
Aattenuator
Bamplifier
Ctank circuit
Dfeedback
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An amplifier with efficiency 85% is likely to be
Aclass A
Bclass B
Cclass AB
Dclass C
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What is the phase difference between the output and input voltage of a CE amplifier?
A180 deg
B270 deg
C0 deg
D90 deg
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Class C operation is preferred in oscillators because
Ait is more efficient
Bit gives larger outputs
Cit produces square waves
Dit increases stability
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A type of oscillator which are composed of one or more amplifying devices with some frequency-determining networks introducing positive feedback at a particular frequency so that oscillation is sustained at that frequency.
Asinewave oscillator
Bsquare-wave oscillator
Crelaxation oscillator
Dlimiter
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What is the desired input impedance of a transistor?
Alow
Bvery low
Chigh
Dvery high
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What is the maximum efficiency of class B?
A50%
B90%
C60.5%
D78.5%
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In an LC circuit, when the capacitor energy is maximum, the inductor energy is
Amaximum
Bminimum
Chalf-way between maximum and minimum
Dzero
#256📘 reviewer_appMedium
What is the approximate gain of an amplifier with negative feedback?
Athe feedback factor
Bthe reciprocal of feedback factor plus one
Cthe reciprocal of feedback factor
Dthe feedback factor plus one
#257📘 reviewer_appEasy
The operating point in a transistor amplifier moves along _____ when an ac signal is applied.
Adc load line
Bac load line
Cboth dc and ac load lines
Dcut-off
#258📘 reviewer_appEasy
An oscillator converts
Aac power into dc power
Bdc power into ac power
Cmechanical power into ac power
Delectrical power into mechanical power
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What is the active device in a transistor oscillator?
ALC tank circuit
Bbiasing circuit
Ctransistor
Dfeedback circuit
#260📘 reviewer_appEasy
When the collector supply is 5 V, then collector cut off voltage under dc conditions is