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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : Which amplifier will be preferred for highest gain? A) Darlington's pair B) Cascade amplifier C) Cascode amplifier D) Depends on the circuitry
Last Answer : C) Cascode amplifier
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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 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 : 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 : 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 : Current gain of a transistor which has collector current of 10 mA and a base current of 40 micro Ampere is: (a) 25 (b) 250 (c) 2500 (d) 25000
Last Answer : b) 250
Description : A 20 ohm resistor and a 60 ohm resistor are connected in parallel to a voltage source. If the current in the 60 ohm resistor is one ampere, the current in the 20 ohm resistor will be: w) 1/3 ampere x) 2/3 ampere y) 1 ampere z) 3 amperes
Last Answer : ANSWER: Z -- 3 AMPERES
Description : Ten Coulombs of charge flowing through a wire per second is equal to: w) 100 Amperes x) 10 Ampere y) 1 Amperes z) 0.1 Amperes
Last Answer : ANSWER: X -- 10 AMPERES
Description : What power is consumed by a heating element using a current of 20 amperes at 120 volts? A. 20 watts B. 66.67 watts C. 720 watts D. 2400 watts
Last Answer : Answer: D
Description : A stone is dropped into a deep shaft without any initial velocity. The sound of the stone hitting the bottom is heard after 4 seconds. If the velocity of sound is 330 m/sec the depth of the shaft will be a.33.1 m b.660 m c.165 m d.66.2 m e.330 m
Last Answer : d. 66.2 m
Description : Which of the following precautions should be taken when a blown fuse, rated at 10 amperes, is replaced? A. Short out the fuse before removing it from the circuit. B. Use needle-nose pliers to ... D. Fuses of 10 ampere rating and less are virtually harmless when energized and may be handled freely.
Last Answer : Answer: C
Description : A lead-acid battery can deliver 20 amperes continuously for 10 hours with an ampere-hour rating of ____________. A. 20 B. 40 C. 200 D. 400
Description : Battery capacities are given in _____________. A. volts B. volt-amperes C. volt-hours D. ampere-hours
Description : Power transformers are rated in _____________. A. kilowatts B. ampere-turns C. kilowatt-volts D. kilovolt-amperes
Description : When current of one ampere is flowing across any cross-section of wire in one second, then the quantity of charge is said to be: (a) One coulomb (b) Three coulomb (c) One micro-coulomb (d) None of above
Last Answer : (a) One coulomb
Description : The number of micro amperes in 2 milli amperes is? A.2 μA B.20 μA C.200 μA D.2,000 μA
Last Answer : The number of micro amperes in 2 milli amperes is? A.2 μA B.20 μA C.200 μA D.2,000 μA
Description : What current is required to light two 75 watt lamps and one 40 watt lamp when connected in series to a 120 volt power source? A. 0.161 amperes B. 0.631 amperes C. 1.583 amperes D. 6.199 amperes
Description : The wavelength of a visible extends from ∙ A. 0.8 to 1.6 um ∙ B. 400 to 750 nm ∙ C. 200 to 660 nm ∙ D. 700 to 1200 nm
Last Answer : B. 400 to 750 nm
Description : For a given base voltage and base volt-amperes, the per unit impedance value is x. For the doubled base values of both voltage and volt-amperes, the per unit impedance will be (a) 2x (b) 0.25x (c) 0.5x (d) no change
Last Answer : Answer is 2x Base impedance =(base voltage) ²/base current
Description : A current of 6 amperes flows through a 2 ohm resistor for 30 seconds. How many coulombs of charge have passed through the resistor?
Last Answer : ANSWER: 180 COULOMBS
Description : An electrical component is connected across a 120 volt 60 hertz AC supply. What is the current drawn by the component if the impedance is 200 ohms? A. 0.01 amperes B. 0.60 amperes C. 1.67 amperes D. 100 amperes
Last Answer : Answer: B
Description : The distance between a generator and its load is 100 feet. What would be the approximate total voltage drop across a two wire supply cable if the current were 5.5 amperes and the resistance of the wire were 2.525 ohms per 1,000 feet? A. 0.5 volts B. 1.38 volts C. 1.90 volts D. 2.77 volts
Description : In cranking the engine normally motor takes current about a) 300 amperes b) 400 amperesb) 5 0 0 amperes d) 600 amperes
Last Answer : b) 400 amperes