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Introduction to Electronic Emission, Tubes and Power Supplies


Quiz Questions

1. The _____________ is the electron-emitting element of a tube.
Cathode
Anode
2. Diode operation depends upon current flow through the tube.
True
False
3. Factors that limit vacuum tube operation are plate dissipation, maximum average current, maximum peak-plate and current and peak-inverse voltage.
True
False
4. A _________ is basically a diode with a control grid mounted between the plate and the cathode. The control grid gives it the ability to amplify signals.
Triode
Diode
5. Tube biasing is the process of placing a dc voltage, usually negative, on the grid.
True
False
6. The class of operation of an amplifier is not determined by the bias applied to a triode.
True
False
7. _______________is the time required for electrons emitted by the cathode to reach the plate.
Conducting time
Transit time
8. ______________were developed to compensate for the effects of inter electrode capacitance.
Tetrodes
Cathodes
Anodes
9. Pentodes do not suffer from the effects of secondary emission. This is because a negatively charged suppression grid placed between the screen grid and plate forces any electrons emitted back to the plate.
True
False
10. _________ tubes contain a small amount of gas that ionizes and reduces the internal resistance of the tubes.
Gas filled
Planar
11. UHF Tubes are special-purpose tubes designed to operate at ultrahigh frequencies between______________ with minimum effect from transit time limitations.
100 to 1000 MHz
200 to 2000 MHz
300 to 3000 MHz
12. Figure 3-1 represents ___________________.
Block diagram of a transformer
Block diagram of a power supply
Block diagram of a generating system
13. Therefore, current or voltage pulses with a value of .318 of the peak value have the same effect on the load as a steady voltage or current.
True
False
14. _________________rectifier circuit uses two diodes (V1 and V2) and a center-tapped transformer (T1).
Half wave
Full wave
15. How many types of filter circuits exist?
Three
Four
Five
16. What is the most basic type of filter?
Resistor
Inductor
Capacitor

17. ___________ are designed to smooth, or filter, the ripple voltage present on the pulsating dc output of the rectifier.
Rectifier circuits
Filter circuits
18. PI-type filters use both _________ and ____________filters connected in a pi-type configuration.
Resistive & inductive
Capacitive & resistive
Capacitive & inductive
19. Shunt regulators do not use a variable resistance placed in parallel with the load.
True
False
20. Ballast tube is normally used to control _________ surges.
Current
Voltageh