NAVEDTRA 14188A, NEETS Mod. 16, Ch. 2

Question 1

What is the product of the potential in volts and the current in amperes?

Answer 1

Watt

Question 2

Power measurements for af circuits are usually indicated in terms of decibels (dB) or decibels referenced to what?

Answer 2

1 milliwatt (dBm)

Question 3

Which type of unit expresses the logarithmic ratio between the input and the output of any given component, circuit, or system?

Answer 3

Bel

Question 4

You can convert any figure expressed in bels to decibels by multiplying that figure by what?

Answer 4

10

Question 5

Which type of loading device undergoes changes of resistance as changes in dissipated power occur?

Answer 5

Bolometer

Question 6

What are the two types of bolometers?

Answer 6

Barretter and Thermistor

Question 7

A thermistor bridge circuit includes other thermistor elements, referred to as what?

Answer 7

Compensating thermistors

Question 8

The rotating frequency (speed in revolutions per minute) of armatures in electric motors and engine-driven generators, as well as the blade speed in turbines, is measured with devices called tachometers, stroboscopes, and what else?

Answer 8

Strobotacs

Question 9

Which type of instrument measures the rate at which a shaft is turning?

Answer 9

Tachometer

Question 10

What are the two common types of portable tachometers?

Answer 10

Centrifugal and Chronometric

Question 11

Which type of instrument allows you to view rotating or reciprocating objects intermittently and produces the optical effect of a slowing down or stopping motion?

Answer 11

Stroboscope

Question 12

Which type of electronic flash device is the flash duration is very short (a few millionths of a second)?

Answer 12

Strobotac

Question 13

Which type of device is the simplest type of frequency meter?

Answer 13

Vibrating-reed

Question 14

What are used as filters for the passage or rejection of specific frequencies?

Answer 14

Tuned circuits

Question 15

Which type of circuit offers a low impedance to currents of the particular frequency to which the circuit is tuned and a relatively high impedance to currents of all other frequencies?

Answer 15

Series-tuned

Question 16

Which type of frequency meters are used to measure the frequency of the unknown signal by matching the unknown signal with a locally generated signal of the same frequency obtained from a calibrated, precision oscillator?

Answer 16

Heterodyne

Question 17

Which calibrated resonant circuits are used to measure frequency?

Answer 17

Wavemeters

Question 18

Which type of wavemeter is the type most commonly used?

Answer 18

Cavity

Question 19

Which high-speed electronic counter has an accurate, crystal-controlled time base?

Answer 19

Electronic frequency counter

Question 20

What is commonly used for the analysis of waveforms generated by electronic equipment?

Answer 20

Cathode-Ray Oscilloscope

Question 21

Which type of device sweeps over a band of frequencies to determine what frequencies are being produced by a specific circuit under test and the amplitude of each frequency component?

Answer 21

Spectrum Analyzer

Question 22

Transistors, however, are capable of operating in excess of how many hours at maximum rating without failure?

Answer 22

30,000

Question 23

What can be used to graphically display the back-and-forward resistance characteristics of a crystal diode?

Answer 23

Oscilloscope

Question 24

Tube failures account for over what percent of the failures in electron-tube equipments?

Answer 24

90

Question 25

Transistors are easily damaged by high current; therefore, resistance measurements must not be taken with an ohmmeter that provides a maximum current output in excess of what?
1 milliampere

Answer 25

Transistors are easily damaged by high current; therefore, resistance measurements must not be taken with an ohmmeter that provides a maximum current output in excess of what?
1 milliampere