Gibilisco - Electron Tubes
- 1.A major difference between a triode tube and an N-channel FET is the fact that
- A.
Triodes work with lower signal voltages.
- B.
Triodes are more compact.
- C.
Triodes need higher power-supply voltages.
- D.
Triodes don’t need filaments.
- 2.The control grid of a vacuum tube is the electrical counterpart of the
- A.
Source of a MOSFET.
- B.
Collector of a bipolar transistor.
- C.
Anode of a diode.
- D.
Gate of an FET.
- 3.In a tetrode tube, the charge carriers are
- A.
Free electrons, which pass among the electrodes.
- B.
Holes, which are conducted within the electrodes.
- C.
Holes or electrons, depending on whether the device is P type or N type.
- D.
Nuclei of whatever elemental gas happens to exist in the tube.
- 4.Which factor is most significant in limiting the maximum frequency at which a tube canoperate?
- A.
The power-supply voltage
- B.
The capacitance among the electrodes
- C.
The physical size of the tube
- D.
The current passing through the filament
- 5.In a tube with a directly heated cathode,
- A.
The filament is separate from the cathode.
- B.
The grid is connected to the filament.
- C.
The filament serves as the cathode.
- D.
There is no filament.
- 6.In a tube with a cold cathode,
- A.
The filament is separate from the cathode.
- B.
The grid is connected to the filament.
- C.
The filament serves as the cathode.
- D.
There is no filament.
- 7.A screen grid enhances tube operation by
- A.
Increasing the gain, helping the circuit to oscillate more easily.
- B.
Decreasing the plate voltage required to produce oscillation.
- C.
Minimizing the risk that a tube amplifier will break into oscillation.
- D.
Pulling excess electrons from the plate.
- 8.A tube with three grids is called a
- A.
Triode.
- B.
Tetrode.
- C.
Pentode.
- D.
Hexode.
- 9.A tube with four grids is called a
- A.
Triode.
- B.
Tetrode.
- C.
Pentode.
- D.
Hexode.
- 10.An advantage of a grounded-grid RF power amplifier over a grounded-cathode RF poweramplifier is the fact that the grounded-grid circuit
- A.
Has excellent sensitivity.
- B.
Exhibits high input impedance.
- C.
Produces little or no noise in the input.
- D.
Is more stable.
- 11.A heptode tube has
- A.
One plate.
- B.
Two plates.
- C.
Three plates.
- D.
Four plates.
- 12.The electron gun in a CRT is another name for its
- A.
Cathode.
- B.
Anode.
- C.
Control grid.
- D.
Screen grid.
- 13.The electron beam in an electrostatic CRT is bent by
- A.
Magnetic fields produced by current-carrying coils.
- B.
Electric fields produced by charged electrodes.
- C.
A variable voltage on the screen grid.
- D.
Visible light striking the electrodes.
- 14.A grounded-grid RF power amplifier
- A.
Requires more driving power, for a given RF power output, than a grounded-cathode RF power amplifier.
- B.
Requires less driving power, for a given RF power output, than a grounded-cathode RF power amplifier.
- C.
Oscillates at a more stable frequency than a grounded-cathode RF power amplifier.
- D.
Oscillates at a less stable frequency than a grounded-cathode RF power amplifier.
- 15.In a Klystron, the electron-beam density varies as a result of
- A.
Amplitude modulation.
- B.
Pulse modulation.
- C.
Velocity modulation.
- D.
Frequency modulation.
- 16.A vidicon camera tube is noted for its
- A.
Poor signal-to-noise ratio.
- B.
Large size and heavy weight.
- C.
Slow response to image movement in dim light.
- D.
Excellent selectivity and electrical ruggedness.
- 17.The plate in a tetrode tube is normally connected to
- A.
A positive dc power-supply voltage.
- B.
A negative dc power-supply voltage.
- C.
Electrical ground.
- D.
RF ground.
- 18.The screen grid in a tetrode tube is normally connected to
- A.
A positive dc power-supply voltage.
- B.
A negative dc power-supply voltage.
- C.
Electrical ground.
- D.
RF ground.
- 19.Which of the following is most suitable for measuring the intensity of dim light?
- A.
A triode gas-filled tube
- B.
A photomultiplier tube
- C.
An electrostatic CRT
- D.
An electromagnetic CRT
- 20.In a dissector tube, the aperture size is directly related to the
- A.
Operating voltage.
- B.
Signal-to-noise ratio.
- C.
Response speed.
- D.
Image resolution.
Related Topics
Recent Quizzes
Featured Quizzes
Popular Topics
Back to top