Description : The suppressor grid is added to a tetrode to reduce what undesirable characteristic of tetrode operation?
Last Answer : Secondary emission.
Description : What undesirable effect does the screen grid in a tetrode create?
Last Answer : Secondary emission, and noise.
Description : What type of feedback is usually caused by the base-to collector interelectrode capacitance?
Last Answer : Degenerative or negative
Description : What type of feedback is usually caused by interelectrode capacitance?
Last Answer : Negative (degenerative) feedback
Description : Moving tube electrodes apart to decrease interelectrode capacitance causes an increase in the effect of what property?
Last Answer : Transit time
Description : What happens to the impedance of interelectrode capacitance as frequency increases?
Last Answer : Impedance decreases.
Description : What effect does the shielding of the screen grid by the control grid have on plate current in beam-forming tetrodes?
Last Answer : By increasing the number of electrons that reach the plate, plate current is increased.
Description : Basically, a magnetic amplifier is a saturable reactor with the addition of _____________. A. AC to the bias winding B. variable capacitance to all windings C. eddy current protectors D. a rectifier in the load circuit
Last Answer : Answer: D
Description : Once ionization has occurred in a thyratron, what control does the control grid have over the tube’s operation?
Last Answer : None.
Description : What is the major difference in grid construction between power pentodes and conventional pentodes?
Last Answer : Conventional pentodes have a staggered grid arrangement, while power pentodes have a shielded grid arrangement.
Description : What serves as a grid in a magnetron?
Last Answer : A magnetic field.
Description : How does transit time affect the relationship of the grid voltage and the plate current at high frequencies?
Last Answer : Transit time causes the grid voltage and plate current to be out of phase
Description : In a circuit using grid-leak biasing, the coupling capacitor (Cc) chargcharge path?
Last Answer : rkg, the cathode to grid resistance.
Description : Why the control grid of a triode amplifier is negatively biased?
Last Answer : To prevent them from drawing grid current.
Description : Why does the grid have a greater effect than the plate on electron flo
Last Answer : Because it is closer to the cathode.
Description : A tube has a transconductance of 800 mhos and a load resistor of 50 kohms. When control grid voltage varies by 6 volts, the plate voltage will vary by what amount?
Last Answer : 240 volts.
Description : If the mu of a tube is 85 and the signal at the control grid is 4 volts ac, the plate voltage will vary by what amount?
Last Answer : 340 volts.
Description : The plate voltage of a tube will vary 126 volts when a 3-volt ac signal is applied to the control grid. What is the gain of this tube?
Last Answer : 42.
Description : When is a control-grid modulator used?
Last Answer : In cases when the use of a minimum of af modulator power is desired.
Description : When an unknown capacitance is tested with a bridge, what is the value of Cx if R1 equals 70 ohms, R2 equals 150 ohms, and Cs equals 550 microfarads?
Last Answer : 256 microfarads.
Description : What effect does an increase in capacitance have on a capacitor’s opposition to current flow?
Last Answer : Opposition to current flow decreases.
Description : When the reverse bias on a varactor is increased, what happens to the effective capacitance?
Last Answer : Capacitance decreases.
Description : A transmission line is said to have distributed constants of inductance, capacitance, and resistance along the line. What units of measurement are used to express these constants?
Last Answer : Inductance is expressed in micro henrys per unit length, capacitance is expressed in picofarads per unit length, and resistance is expressed in ohms per unit length.
Description : . What are two of the three physical factors that determine the values of capacitance and inductance of a transmission line?
Last Answer : (1) Type of line used, (2) dielectric in the line, and (3) length of line.
Description : Trade-offs between competing effects are necessary for high speed response. Which competing effect (fast transit time, low capacitance, or high quantum efficiency) requires a thin active area?
Last Answer : Fast transit time.
Description : Should the capacitance of the photodetector be kept small or large to prevent the RC time constant from limiting the response time?
Last Answer : Small
Description : What happens to the value of XC as capacitance increases
Last Answer : XC decreases.
Description : Examine the three capacitors shown below. What is the capacitance of each?
Last Answer : a. 26µF or 260,00pF b. 630pF c. 9600pF
Description : State three factors that affect the capacitance of a capacitor.
Last Answer : a. The area of the plates. b. The distance between the plates. c. The dielectric constant of the material between the plates.
Description : At a grid sub stations the voltage is stepped up to reduce loss of which thing? -Do You Know?
Last Answer : answer:
Description : Eliminate, Reduce, Raise, Create (ERRC) Grid is a tool used in which of the following? A. Benchmarking B. Blue Ocean Strategy C. Business Process Re-engineering D. Balanced Scorecard
Last Answer : Blue Ocean Strategy
Description : The ___________ of a CRO controls the brightness of the spot formed on the screen a) Filament b) Grid c) Deflection plates d) Cathode
Last Answer : b) Grid
Description : In a TDR system connected for addition in what direction will the TDR rotor field turn when the TX rotor to which it is connected turns counterclockwise?
Last Answer : Clockwise.
Description : What connections in a TDR system are reversed to set up the system for addition?
Last Answer : . The R1 and R3 leads between the TDR rotor and the TX to which it is connected.
Description : What connections in a TDX system are reversed to set up the system for addition?
Last Answer : The number and type of synchro receivers, the mechanical loads on these receivers and the operating temperatures of both the transmitter and receivers.
Description : In addition to stepping up or stepping down the input line voltage, what additional purpose does the transformer serve?
Last Answer : . It isolates the chassis from the power line.
Description : What type of instructions permit addition, subtraction, multiplication, and division?
Last Answer : Arithmetic.
Description : In addition to a flat top, what characteristics must a modulator pulse have?
Last Answer : Steep leading and trailing edges.
Description : In addition to recovery time, what determines the minimum range of a radar set?
Last Answer : Pulse width
Description : In addition to a primary coating, manufacturers add a layer of buffer material for what reasons?
Last Answer : To provide additional mechanical protection and preserve the fiber's inherent strength.
Description : Addition of stabiliser during PVC manufacture is done to (A) Improve its impact strength (B) Improve its elasticity (C) Reduce the melt viscosity & glass transition temperature (D) Prevent its thermal degradation
Last Answer : (D) Prevent its thermal degradation
Description : One of the steps during refining of cane sugar consists of addition ofhydrated lime to the sugar syrup followed by carbonation of the resulting solution. The purpose of this step is to (A) Adjust ... (C) Reduce the viscosity of the syrup (D) Improve the rate of crystallisation of sugar
Last Answer : (A) Adjust the pH of the syrup
Description : What three factors must be considered in the transmission of a surface wave to reduce attenuation?
Last Answer : (a) electrical properties of the terrain (b) frequency (c) polarization of the antenna
Description : Fiber optic connectors can reduce system performance by increasing what two types of noise?
Last Answer : Modal and reflection.
Description : Name the procedure used to reduce excessive arcing in a magnetron?
Last Answer : Baking in.
Description : Flat panel displays are designed to reduce what problem of a crt display?
Last Answer : Reduce the depth of the crt display caused by the length of the tube.
Description : What element controls the number of electrons striking the screen?
Last Answer : Control grid.
Description : In applications where electronic waveforms are displayed on a CRT screen, the input signal is normally applied to what CRT element?
Last Answer : The vertical-deflection plate.