Flashcards in NAVEDTRA 14188A, NEETS Mod. 16, Ch. 2 Deck (25)
What is the product of the potential in volts and the current in amperes?
Power measurements for af circuits are usually indicated in terms of decibels (dB) or decibels referenced to what?
1 milliwatt (dBm)
Which type of unit expresses the logarithmic ratio between the input and the output of any given component, circuit, or system?
You can convert any figure expressed in bels to decibels by multiplying that figure by what?
Which type of loading device undergoes changes of resistance as changes in dissipated power occur?
What are the two types of bolometers?
Barretter and Thermistor
A thermistor bridge circuit includes other thermistor elements, referred to as what?
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?
Which type of instrument measures the rate at which a shaft is turning?
What are the two common types of portable tachometers?
Centrifugal and Chronometric
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?
Which type of electronic flash device is the flash duration is very short (a few millionths of a second)?
Which type of device is the simplest type of frequency meter?
What are used as filters for the passage or rejection of specific frequencies?
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?
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?
Which calibrated resonant circuits are used to measure frequency?
Which type of wavemeter is the type most commonly used?
Which high-speed electronic counter has an accurate, crystal-controlled time base?
Electronic frequency counter
What is commonly used for the analysis of waveforms generated by electronic equipment?
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?
Transistors, however, are capable of operating in excess of how many hours at maximum rating without failure?
What can be used to graphically display the back-and-forward resistance characteristics of a crystal diode?
Tube failures account for over what percent of the failures in electron-tube equipments?