Description : Which of the following circuit would be preferred for a 455 kHz IF amplifier? A) A resistance loaded B) Double tuned transformer C) Video amplifier D) Class C
Last Answer : B) Double tuned transformer
Description : In a resistance loaded amplifier, the gain decreases a high frequencies because A) Of decreasing reactance of the stray CT B) Increasing reactance of the stray CT C) Increasing reactance of CC D) Decreasing reactance of CC.
Last Answer : D) Decreasing reactance of CC.
Description : What conditions are required for an amplifier to oscillate A) There must be feedback B) The feedback must be in phase C) The gain must be greater than the loss D) All the above are regd.
Last Answer : B) The feedback must be in phase
Description : In an amplifier if conductor during the cycle is from 0 to 90° and again from 180° to 270°, the amplifier will be termed as A) Class A B) Class B C) Class C D) Class AB.
Last Answer : B) Class B
Description : Which of the following methods cannot be used to increase the bandwidth for cascaded RF amplifier stages? A) Wave traps in each stage B) Stagger tuning C) A shunt damping resistor across each tuned circuit D) Doubled tuned transformers with tighter coupling
Last Answer : A) Wave traps in each stage
Description : A push pull amplifier balances out A) Odd harmonics B) Even harmonics C) Both odd as well as even harmonics D) Neither odd nor even harmonics.
Last Answer : A) Odd harmonics
Description : In an amplifier the collector voltage equals the full V+ of 28 V instead of the normal 12 V which of the following can be the trouble? A) RL is open B) Cc is open C) RE is open D) CE is shorted.
Last Answer : B) Cc is open
Description : An ideal voltage amplifier should have A) Ri = 0, R0 = 0 B) Ri = 0, R0 =∞ C) Ri = ∞, R0 = 0 D) Ri = ∞, R0 = ∞.
Last Answer : C) Ri = ∞, R0 = 0
Description : In a resistance loaded, RC coupled amplifier the dc component is blocked by A) Load resistance RL B) Coupling capacitor, CC C) RB D) The transistor.
Last Answer : B) Coupling capacitor, CC
Description : If the operating point of an NPN transistor amplifier is selected in saturation region, it is likely to result in A) Thermal runaway of transistor B) Clipping of output in the positive half of the ... for high dc collector supply D) Clipping of output in the negative half of the input signal
Last Answer : B) Clipping of output in the positive half of the input signal
Description : As compared to a CB amplifier, a CE amplifier has A) Lower current amplification B) Higher current amplification C) Higher input resistance. D) Both (B) & (C)
Last Answer : D) Both (B) & (C)
Description : Which of the following is not true: A) An oscillator is a circuit that converts DC to AC B) An oscillator is an amplifier that supplies its own input signal C) All oscillators generate sine waves D) In phase feedback is called positive Feedback
Last Answer : C) All oscillators generate sine waves
Description : The Bandwidth of an RC-coupled amplifier is limited by: A) coupling capacitors at the low frequency end and bypass capacitors at the high frequency end B) coupling capacitors at the high frequency ... at the low frequency end and bypass as well as coupling capacitors at the high frequency end.
Last Answer : C) bypass and coupling capacitors at the low frequency end and shunt capacitors at the high frequency end and
Description : The Darlington pair consists of the following two stages A) CE and CC B) Both C) Both CC D) CE and CB
Last Answer : C) Both CC
Description : Common base configuration is little used because A) It has low input impedance B) It has high input impedance C) It does not heat up D) It has very high gain.
Last Answer : A) It has low input impedance
Description : The major function of transistor. Q2 is A) It provides voltage gain B) It provides the feedback signal C) It isolates the oscillator from loading effects D) It provides a phase shift.
Last Answer : ) It provides a phase shift.
Description : For Cascode amplifier the output impedance becomes
Last Answer : For Cascode amplifier the output impedance becomes very high
Description : The change in base current will be A) 0.66 micro ampere B) 6.6 micro amperes C) 66 micro amperes D) 660 micro amperes.
Last Answer : A) 0.66 micro ampere
Description : Which distortion is least objectionable in case of audio amplifers? A) Phase distortion B) Frequency distortion C) Harmonic distortion D) Inter modulation distortion.
Last Answer : A) Phase distortion
Description : Which of the following contributes to harmonics distortion in amplifiers? A) Positive feedback B) Presence of noise C) Defective active device D) Non linearity in active device.
Last Answer : D) Non linearity in active device.
Description : A IGFET is a A) Linear device B) Square law device C) Half power device D) 3/2 power law device.
Last Answer : B) Square law device
Description : An FET has a gate source bias of 2 V. The ac input signal is ± 1.2 V. The class of operation is A) A B) B C) C D) AB
Last Answer : D) AB
Description : Which of the following combinations has no phase inversion of the signal? A) Two CE stages B) CE and CC stages C) Three CE stages D) CE stage and emitter follower.
Last Answer : A) Two CE stages
Description : Foldback current limiting has the advantage of A) Better pass transistor protection for long term overloads B) A defined turn on point C) Circuit simplicity D) All of the above.
Last Answer : A) Better pass transistor protection for long term overloads
Description : A crow bar is a power supply circuit that provides A) Conventional current limiting B) Foldback current. limiting C) Temperature control D) Voltage limiting.
Last Answer : D) Voltage limiting.
Description : Current limited power supplies can prevent damage to A) Rectifier diodes and power transformers. B) Pass transistors C) Other circuits in the system D) All of the above.
Last Answer : D) All of the above.
Description : In general, MOV devices are used to protect electronic equipment from dangerous operating conditions such as A) High temperatures B) Line transients C) Over current D) All of the above.
Description : Load regulation is a measure of a power supplies ability keep a constant output under conditions of changing A) Line voltage B) Current demand C) Temperature D) Oscillator frequency.
Last Answer : A) Line voltage
Description : What is the phase relationship of the signal at the collector of Q2 to the signal at the collector of Q, A) 0° B) 90° C) 180° D) 360°.
Last Answer : C) 180°
Description : A series mode crystal is marked 10.000 MHz., It is used in a circuit that operates the crystal in its parallel mode. The circuit can be expected to A) Run below 10 MHz B) Run at 10 MHz C) Run above 10 MHz D) Not oscillate.
Last Answer : C) Run above 10 MHz
Description : Six (6) MHz crystal oscillator has a stability of 1 part in 106. The largest frequency error expected of this crystals A) 0.06 Hz B) 0.6 Hz C) 6 Hz D) 60 Hz.
Last Answer : C) 6 Hz
Description : An oscillator that uses crystal control should be A) Frequency stable B) useful only at low frequencies C) AVFO D) none of the above.
Last Answer : A) Frequency stable
Description : The ideal characteristic of a voltage stablizer is A) constant output voltage with low internal resistance B) constant output current with low internal resistance C) constant output voltage with high internal resistance D) constant internal resistance with variable output voltage.
Last Answer : A) constant output voltage with low internal resistance
Description : Which amplifier will be preferred for highest gain? (1) Darlington pair (2) Cascade amplifier (3) Cascode amplifier (4) Depends on the circuitry
Last Answer : Cascode amplifier will be preferred for highest gain.
Description : State the need of cascade amplifier and draw circuit diagram of 2-stage direct coupled amplifier.
Last Answer : Need:- The voltage (or power) gain, obtained from a single stage small signal amplifier, is limited. Therefore, it is not sufficient for all practical applications. Therefore, in order to obtain greater voltage and power gain, cascade amplifiers are used.
Description : State the need of cascade amplifier.
Last Answer : Most systems a single transistor amplifier does not provide sufficient gain or bandwidth or will not have the correct input or output impedance matching. Hence cascade amplifier is use which consist more than one stages of amplification.
Description : The voltage gain of a common base amplifier depends on 1. Load resistor RL 2. input resistance of transistor 3. Ac alpha 4. All the above
Last Answer : The voltage gain of a common base amplifier depends on 1. Load resistor RL 2. input resistance of transistor 3. Ac alpha 4. All the above
Description : In the ideal closed loop operational amplifier, the gain depends on (A) value of the series component (B) value of the feedback component (C) on the operational amplifier itself (D) both A and B
Last Answer : In the ideal closed loop operational amplifier, the gain depends on (A) value of the series component (B) value of the feedback component (C) on the operational amplifier itself (D) both A and B
Description : The voltage gain of a common -source JFET amplifier depends up on its (1) Input impedance (2) Amplification factor (3) Dynamic drain resistance (4) Drain load resistance
Last Answer : B
Description : If you have available number of power amplifiers with a gain of 100 each, how many such amplifiers do you need to cascade to give an overall gain of 60 dB? A. 3 B. 4 C. 5 D. 2
Last Answer : A. 3
Last Answer : For an amplifier, the coupling method which gives the highest gain is Transformer coupling.
Description : What type of desktop computer does not contain a tower and instead uses the same case to house the display and the processing circuitry?
Last Answer : And All-in-one.
Description : The earth-wire of a cable is connected to – (1) the outer metallic body of the appliance (2) the fuse of the appliance (3) the filament of the appliance (4) short circuitry of the appliance
Last Answer : (2) the fuse of the appliance Explanation: Earth wire prevents Electric shocks. It is connected to the electrical cable of an appliance to prevent electric shocks. Actually it has very low resistance and allows current to pass through it easily.
Description : First Generation computers used ______ for Circuitry and ________ for memory (A) Transistor and Magnetic Core (B) IC and Magnetic Memory (C) Vacuum tubes and Magnetic drum (D) IC and Magnetic Core
Last Answer : (C) Vacuum tubes and Magnetic drum
Description : If the supply voltage is 220 volts 60 Hz, what is the operating voltage of the motor controller circuitry illustrated? EL-0011 A. 110 volts DC B. 110 volts AC C. 220 volts DC D. 220 volts AC
Last Answer : Answer: D
Description : The symbol at coordinates '15R' in the illustration indicate a connection to ___________. EL-0100 A. the analog circuitry common bus B. ground C. the vessel's hull D. the console's chassis
Last Answer : Answer: A
Description : The symbol at coordinates '11R' in the illustration indicate a connection to _____________. EL-0100 A. ground B. the console chassis C. the digital circuitry common bus D. earth through the vessel's hull
Last Answer : Answer: C
Description : In electronic circuits, DC voltages can be positive (+) or negative (-) when measured with respect to the _________. A. printed circuit board 'common' trace B. chassis, console frame or hull 'ground' C. analogue or digital circuitry 'common' bus D. all of the above
Description : In electronic circuitry, the abbreviation 'PCB' commonly means ______________. A. pulse coded binary B. printed circuit board C. poly-coated braid D. personal computer bits
Last Answer : Answer: B
Description : As a general rule, the first troubleshooting action to be taken in checking faulty electric control devices is to _____________. A. draw a one line diagram of the circuitry B. test all fuses and measure the line voltage C. take megger readings D. insulate the apparatus from ground