Card Set Information
Which of the following types of tubes would be used as a voltage amplifier in an electronic circuit?
Multielectrode tubes are normally classified according to the number of
grids contained in the tube
How many grids are there in a pentagrid tube?
What advantage(s) does the in-line grid arrangement of the power pentode have over the staggered grid arrangement of the conventional pentode?
Higher efficiency and higher power output
Which of the following is an advantage that a power pentode has over a conventional pentode?
Greater sensitivity to small signals
What is the primary purpose of the beam-forming plates in the beam power tube?
To concentrate the electrons into a beam
Which of the following is a name given to the variable-mu tube?
Which of the following is an advantage of the variable-mu tube over conventional tubes?
It can amplify large input signals without distortion
What is the only difference between a remote-cutoff tube and a sharp-cutoff tube?
The spacing of the grid wires
Which of the following is the BEST method for reducing transit time in uhf tubes?
Increasing the voltage on the electrodes
Which of the following is a disadvantage of uhf tubes?
They have reduced power-handling capabilities
What is the only physical difference between the doorknob tube and the acorn tube?
Why is the metallic ring of the planar tube grounded?
To eliminate unwanted rf signals
The metallic shell capacitive ground of a planar tube serves as what kind of capacitor in a cathode-bias circuit?
What is the major difference between the oil can tube and the lighthouse tube?
The oilcan tube has cooling fins;the lighthouse tube does not
Which of the following is an advantage that an oilcan tube has over a lighthouse tube?
The oilcan tube can handle more power
The plate potential at which ionization occurs is known as the ionization point.Which of the following is also a name for this process?
What name is given to the value of plate voltage at which ionization stops?
When a gas-filled triode ionizes, the grid loses control and the tube then functions as what type of tube?
After the gas-filled triode ionizes and the grid loses control, which of the following methods is used to stop the conduction of the tube?
Removing the plate potential
What is the name given to the gas-filled triode?
For what minimum amount of time must the filaments of a mercury-vaportube have voltage applied before the plate voltage is applied to the tube?
Which of the following conditions is/are responsible for the soft, blue glow of the gas-filled triode?
The tube is ionized
Which of the following types of tubes is normally used as a voltage regulator?
For a cold-cathode tube, how does the voltage regulator maintain a constant voltage drop across the tube?
By changing the resistance of the tube as current flow varies
The electron gun of the CRT serves which of the following functions?
Concentrates electrons into a beam
Which of the following is a description of the grid in a CRT?
A metal cap with a hole in the center
What element of a television CRT is adjusted by the brightness control?
Which of the following elements of the CRT helps prevent the beam of electrons from diverging?
Which of the following elements of a CRT has the highest positive potential?
The accelerating anode
What is the name of the florescent material that coats the inside face of a CRT?
What is the purpose of the aquadag coating in the CRT?
It eliminates the effects of secondary emission
In which of the following equipment would you most likely find a cathode-ray tube?
If deflection were not used in the CRT,what would be viewed on the screen of the tube?
A bright spot in the center
Which of the following types of deflection is used by much of the test equipment in the Navy?
Which of the following elements cause(s) the electron beam to move from left to right on a CRT?
Horizontal deflection plates
Source of electrons
Reduces interelectrode capacitance
Focuses electrons into a beam
Acts as suppressor grid
Displays electron beam
Deflects beam to right
Horizontal deflection plates
Deflects beam to down position
Vertical deflection plates
Eliminates secondary emission
Which of the following actions must you take first before disposing of a cathode-ray tube?
Render the CRT harmless
What is the purpose of adding radioactive material to electron tubes?
The material aids ionization in the tube
Safety precautions and procedures for working with radioactive electron tubes can be found in which of the following publications?
Radiation, Health, and Protection Manual