Description : The constant-speed electrons of an electron bunch in a reflex klystron must remain in the repeller field for what minimum time?
Last Answer : Three-quarter cycle.
Description : What limits the tuning range around the center frequency of a reflex klystron in a particular mode of operation?
Last Answer : The half-power points of the mode.
Description : When the repealer potential is constant, what property of the electron determines how long it will remain in the drift space of the reflex klystron?
Last Answer : Velocity.
Description : Debunching of the electron bunches in the higher modes of a reflex klystron has what effect on output power?
Last Answer : Power is reduced.
Description : What element of the reflex klystron replaces the output cavity of a normal klystron?
Last Answer : The reflector or repeller.
Description : In the illustration, the contacts between terminals 26 and 27 should be closed when _________. EL-0046 A. using one generator in isochronous mode only B. using two or more generators in ... through varying loads in parallel or single operation D. the circuit breaker is closed for that generator
Last Answer : Answer: C
Description : The electrons in the beam of a klystron are speeded up by a high dc potential applied to what elements?
Last Answer : The accelerator grid and the buncher grids.
Description : What is the basic principle of operation of a klystron?
Last Answer : Velocity modulation
Description : In single mode operation, the value of the normalized frequency (V) should remain near the 2.405 level. If the value of V is less than 1, do single mode fibers carry a majority of the power in the core or cladding material?
Last Answer : Cladding material.
Description : Describe working of Reflex Klystron amplifier with a neat diagram.
Last Answer : Operation: It is assumed that the oscillations are set up in the tube initially due to noise or switching transients and these oscillations are sustained by device operation. ... on the reference electron. These bunch transfer maximum energy to the gap to get sustained oscillations.
Description : Reflex klystron is a: (1) Low power generator (2) High power oscillator (3) Low gain amplifier (4) Not an oscillator
Last Answer : Reflex klystron is a: Low power generator.
Last Answer : The modes in a reflex Klystron gives the same frequency but different transit time.
Description : Which of the following statements is true concerning the operation of two alternators in parallel? A. The cycles per second of each alternator are the same. B. Both alternator governors must be set ... be the same on each alternator. D. The load must always be divided equally between alternators.
Last Answer : Answer: A
Description : An AC generator produces 60 Hz at 1800 RPM. If the generator speed is increased to 1830 RPM, the cycles will _____________. A. remain at 60 Hz B. increase to 61 Hz C. decrease to 59 Hz D. increase to 63 Hz
Last Answer : Answer: B
Description : What type of klystron is used as the final stage of a power- amplifier transmitter?
Last Answer : Multicavity klystron.
Description : The cavities of a multicavity klystron are tuned to slightly different frequencies in what method of tuning?
Last Answer : Stagger tuning.
Description : In a multicavity klystron, tuning all the cavities to the same frequency has what effect on the bandwidth of the tube?
Last Answer : The bandwidth decreases.
Description : Which cavity of a three-cavity klystron causes most of the velocity modulation?
Last Answer : The middle cavity.
Description : How is the electron beam of a three-cavity klystron accelerated toward the drift tube?
Last Answer : A large negative pulse is applied to the cathode.
Description : What can be added to the basic two-cavity klystron to increase the amount of velocity modulation and the power output?
Last Answer : Intermediate cavities between the input and output cavities.
Description : A two-cavity klystron without a feedback path will operate as what type of circuit?
Last Answer : Amplifier.
Description : The two-cavity klystron uses what cavity as an output cavity?
Last Answer : The catcher cavity.
Description : What should you do if a klystron becomes gassy?
Last Answer : Restore it to serviceable condition by operating it temporarily at reduced beam voltage.
Description : Which of the following statements is incorrect? (a) Station batteries are used to operate relay only (b) The lightning arresters are basically surge diverters (c) An impedance relay has maximum fault current when fault occurs near the relay (d) A high speed relay has an operation of 1 to 2 cycles
Last Answer : (a) Station batteries are used to operate relay only
Description : The number of cycles in which a high speed circuit breaker can complete its operation is (A) 3 to 8 (B) 10 to 18 (C) 20 to 30 (D) 40 to 50
Last Answer : The number of cycles in which a high speed circuit breaker can complete its operation is 3 to 8
Description : Klystron operation is based on the principle of a) Velocity modulation b) Amplitude modulation c) frequency modulation d) Phase modulation
Last Answer : Klystron operation is based on the principle of Velocity modulation
Description : Why is the pi mode the most commonly used magnetron mode of operation
Last Answer : Greater power output.
Description : The cycles per second developed by the alternator aboard your vessel is determined by _____________. A. the speed of the engine driving the alternator B. the resistance applied to the field rheostat C. the synchronous speed of induction D. the adjustments made to the voltage regulator
Description : The number of cycles per second occurring in AC voltage is known as the _____________. A. phase angle B. frequency C. wave form D. half mode
Description : During which of the transmit or receive cycles are both the tr and atr tubes of a parallelconnected duplexer ionized (arcing)?
Last Answer : Transmit.
Description : The electric field is perpendicular to the "a" dimension of a waveguide in what mode?
Last Answer : TE.
Description : Will fiber coupling loss generally increase or decrease if the mode field diameter of a single mode fiber is decreased?
Last Answer : Increase.
Description : Which of the following should be the FIRST step in removing a generator from parallel operation? A. Trip the generator off the switchboard. B. Turn off all electrical equipment. C. Remove the load from the 'off going' generator. D. Increase the cycles of the generator staying on the line.
Description : The frequency of operation is per minute A. 600 cycles C. 400 cycles B. 100 cycles. D. 200 cycles
Last Answer : 400 cycles
Description : The interaction between an external field and the binding force of an atom causes electrons to do what?
Last Answer : Wobble at a natural resonant frequency.
Description : What causes dc bias energy to be absorbed by avalanche electrons and given up to the microwave field applied to an avalanche transit-time diode?
Last Answer : The negative-resistance property.
Description : What are the electrons called that give up energy to the ac field in a magnetron?
Last Answer : Working electrons.
Description : What is the term used to identify the amount of field strength required to cause the electrons to just miss the plate and return to the filament in a circular orbit?
Last Answer : The critical value of field strength
Description : After 48 hours of a cataract extraction operation, a patient complained of ocular pain and visual loss. On examination, this eye looked red with ciliary injection, corneal oedema and absent red ... a. Secondary glaucoma. b. Anterior uveitis. c. Bacterial endophthalmitis. d. Acute conjunctivitis
Last Answer : ANSWER: C
Description : What precaution should be taken with a vessel's impressed current cathodic protection system after a drydocking period during which the hull has been painted? A. Output currents should be carefully monitored ... slight (10-15%) overcurrent to the anodes should be allowed in order to speed drying.
Description : The field arrangements in waveguides are divided into what two categories to describe the various modes of operation?
Last Answer : Transverse electric (TE) and transverse magnetic (TM).
Description : What is the effect on magnetron operation if the magnetic field strength is too high?
Last Answer : The magnetron will not oscillate.
Description : With the increase in depth, the hydrostatic pressure in an un-accelerated incompressible fluid (in a constant gravitational field) (A) Decreases (B) Increases linearly (C) Increases exponentially (D) Remain constant
Last Answer : (B) Increases linearly
Description : The units of frequency factor in Arrhenius equation (A) Are the same as those of the rate constant (B) Depend on the order of the reaction (C) Depend on temperature, pressure etc. of the reaction (D) Are cycles per unit time
Last Answer : (A) Are the same as those of the rate constant
Description : Which statement best describes the operating principle of a constant-speed propeller? a. As throttle setting is changed by the pilot, the prop governor causes pitch angle of the propeller blades to ... the pilot, the RPM of the engines remains constant as the pitch angle of the propeller changes
Last Answer : b. The propeller control regulates the engine RPM and in turn the propeller RPM
Description : Which of the following types of HPA is not used in earth stations? A. TWT B. Transistor C. Klystron D. Magnetron
Last Answer : D. Magnetron
Description : A major and basic advantage for the use of a klystron. A. High power B. Efficiency C. Lesser noise D. Cheaper
Last Answer : A. High power
Description : A two cavity klystron tube is a (A) velocity modulated tube (B) frequency modulated tube (C) Amplitude modulated tube (D) simple triode
Last Answer : A two cavity klystron tube is a velocity modulated tube