A+ Answers

1. To obtain the greatest possible accuracy in a timing device, you should use a
A. digital timer operated from a crystal-controlled oscillator.
B. 3905 IC operated through an electronic inductor.
C. timer with a unijunction transistor in its circuit.
D. 555 IC operated through an electronic capacitor.
2. You have two methods of locating faults in electronic systems – signal tracing and
A. dumping. C. shaping.
B. injecting. D. squaring.
3. Which one of the following distinguishes a switching power supply from other power
A. Simpler circuitry C. Higher output voltage
B. Smaller transformer D. Elimination of diode rectifier
4 Which of the following devices is connected internally to an output pin of a 555 IC?
A. RS flip-flop C. Reset transistor
B. Power amplifier D. Threshold comparator
5. In troubleshooting a pulse circuit by waveform comparison, you should use
A. a logic probe. C. an oscilloscope.
B. a logic scope. D. a pulser.
6. The most convenient and least time-consuming method of determining an amplifier’s
ability to pass a pulse in a digital circuit is to use the
A. sine-wave test. C. VOM test.
B. square-wave test. D. Wattmeter test.
7. “An output of a high from a logic gate having a high on only one input” describes the
operation of
A. an AND gate. C. an NOR gate.
B. a NOT gate. D. ah XOR gate.
8. A one-shot multivibrator contains two transistors. What is the condition of the
transistors in the standby state?
A. Input transistor is cut off; output transistor is saturated.
B. Output transistor is cut off; input transistor is saturated.
C. Both transistors are saturated.
D. Both transistors are cut off.
9. You would use a logic analyzer to test
A. voltage values. C. an ac amplifier.
B. a digital integrated circuit. D. a system’s power supply.
10. When you hold down the switch in most types of pulsers, the instrument will generate a
A. clock waveform. C. single pulse.
B. sine wave. D. triangular wave.
11. The input trigger pulse to the 3905 timer must be
A. negative-going to pin 1. C. negative-going to pin 2.
B. positive-going to pin 1. D. positive-going to pin 2.