1. The action of a JFET can be compared with that of a
A. pentode
B. tetrode
(C) triode
D. diode
2. What is the equivalent binary of the octal number 673?
A. 101111101
(B) 110111011
C. 110110101
D. 110111111
3. What is the value of the upper resistance limit of a resistor
with color-coding of Brown, Black, Black, Gold?
A. 105 Ω
B. 1.5 Ω
(C) 10.5 Ω
D. 150 Ω
4. How do we obtain the time constant of a series inductor and
resistor circuit?
(A) By dividing the resistance value by the inductance value
B. By multiplying the inductance value by the resistance value
C. by dividing the inductance value by the resistance value
D. By dividing the inductance value by the conductance value
5. How to test whether an oscillator is generating an output?
(A) By checking that the drain current is flowing
B. By checking the value of the signal bias on the gate
C. By checking that the source current is flowing
D. By checking for a high value of the dc supply voltage
6. What is the time constant of a circuit with a charged
capacitor connected across a resistor?
(A) The time required for the capacitor to discharge to a certain
Percentage of its initial voltage
B. Equal to the value of the capacitance divided by the resistance
C. Is the half-life of the capacitor when shunted by the resistor
D. Is equal to the natural period of the circuits’s oscillation
7. How is the frequency of a transistorized multivibrator
determined?
A. By the parameters of the transistor
(B) By the junction capacitance of the transistor
C. By the collector supply voltage
D. By the time constants formed by the coupling capacitors
and the base resistors.
8. When an atom gains an additional electron ______results.
A. positive
(B) negative
C. negative molecule
D. negative neutron
9. Which configuration provides a high degree of isolation between
two stages?
A. Common base
B. Common emitter
C. Common collector
(D) Common grid
10. The impedance of an ac circuits measured in
A. farads
B. henrys
C. siemens
(D) ohms
11. What is the equivalent hexadecimal number of the binary
number 11100101111?
A. 72E
(B) 72F
C. 73F
D. 82E
12. Which electrode of a triode tube can be compared with
the base region of a bipolar transistor?
(A) Control grid
B. Filament
C. Cathode
D. Screen grid
13. Which of the following logic circuits has an operation that
corresponds to two or more switches (or relays) in series?
(A) XOR gate
B. NAND gate
C. AND gate
D. NOR gate
14. Which circuit components has the highest failure rate under normal
Conditions?
A. Transformer
B. Transistor
C. Resistor
(D) Capacitor
15. The inductance of a coil with an air core is directly
proportional to the
A. length of the core
(B) number of turns
C. square of the number of turns
D. cross-sectional area of the wire
16. What is the effect if a bleeder resistor burns out in a power
supply during normal operation?
(A) The diodes could be destroyed
B. The percentage regulation increases significantly.
C. There is no appreciable effect on the output dc voltage.
D. The power transformer will be damaged unless it protected by a fuse.
17. The peak value of a sine wave having an effective value of 20 V is
A. 70.7 V
B. 14.1 V
C. 56.6 V
(D) 28.3 V
18. A varistor is a semiconductor device
A. that can be used to achieve voltage regulation
B. Whose resistance is controlled by the applied voltage
C. that has a high positive temperature coefficient
(D) both A and B correct
19. If a tank ciruit is at the load of a class C amplifier, the
(A) input signal is small
B. efficiency is low
C. output voltage waveform is severely distorted
D. output current waveform is severely distorted
20. The effective values of the source voltage and the source
current are kept constant in an ac circuit. Initially, the current
and voltage are in phase, but as they move out of phase, are
(A) power factor increases
B. apparent power increases
C. true power decreases
D. reactive power decreases
21. What is the total available emf of twelve nickel-cadmium
cells that are connected in series?
A. 12 V
B. 24 V
C. 2.05 V
(D) 15 V
22. What is the resonant frequency of a series RLC circuit consisting of a 6- Ω
resistor, a 5- µH inductor and a 5-pF capacitor?
A. 3.18 MHz
(B) 31.8 MHz
C. 31.8 kHz
D. 318 MHz
23. A “difference of potential ”may also be described as
A. electric power
(B) voltage
C. amperage
D. electron drift
24. A non-conductor is characterized by
A. very few electrons
(B) high energy dissipation
C. a large number of free electrons
D. large amount of skin effect.
25. A wattmeter automatically compensates for
A. power factor
B. overdamping
C. line resistance
(D) power losses
26. RMS is related to peak voltage by the decimal
A. 0.0707
B. 0.636
(C) 0.707
D. 0.770
27. What is the chemical composition of the electrolyte of a
lead-acid storage cell?
A. Sulphur dioxide acid
(B) Sulphuric acid
C. Lead sulphate acid
D. Hydrochloric acid
28. What is usually employed by an RF voltage amplifier
as opposed to an RF power amplifier?
A. Class A bias
(B) Class C bias
C. Cut-off bias
D. Zero bias
29. The transistor common-base amplifier is similar
To what configuration of a vacuum tube?
(A) Grounded-grid amplifier
B. Video amplifier
C. Cathode-follower amplifier
D. Audio amplifier
30. ______ determines the speed of a dc series motor.
A. The brush tension
(B) The field current
C. The load
D. The number of pairs of poles
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