Description : If the constant-speed electrons in a reflex klystron remain in the repeller field for 1 3/4 cycles, what is the mode of operation?
Last Answer : Mode 2.
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 : 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 : 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 : 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 : 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 : 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 : 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 is the basic principle of operation of a klystron?
Last Answer : Velocity modulation
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 : Electrons move at right angles to a magnetic field of `1.5xx10^(-2)` Tesla with a speed of `6xx10^(7)m//s`. If the specific charge of the electron is
Last Answer : Electrons move at right angles to a magnetic field of `1.5xx10^(-2)` Tesla with a speed of `6xx10^ ... C//kg`. The radius of the circular path will be
Description : What portion of an electron gun causes the electrons to accelerate or decelerate?
Last Answer : The buncher grids.
Description : If you're about to speak in front of a bunch of people (presentation, speech), how do you remain cool and not make a complete fool of yourself?
Last Answer : answer:I had to develop public speaking skills which I then used for decades. My trick was to know my subject and then take brief notes on 3 5 index cards. It got easier as time went on. For a worrier, I ... 'll have to do a little research. May I get back to you? See me when I am finished here.
Description : What relationship must exist between the electron beam and the traveling wave for bunching to occur in the electron beam of a twt?
Last Answer : The traveling wave must have a forward velocity equal to or less than the speed of the electrons in the beam.
Description : What will be the effect upon an electron traveling in the opposite direction to the lines of force in an electrostatic field?
Last Answer : The electron will be accelerated.
Description : An electron moves into the electrostatic field between a positive charge and a negative charge. Toward which charge will the electron move?
Last Answer : Toward the positive charge.
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 : A color television set employs a 25,000 volt electron accelerator to produce the picture and potentially harmful radiation which must be shielded against. The main component of this radiation consists ... which penetrate the picture tube x) soft x-rays y) microwaves z) ultraviolet radiation
Last Answer : ANSWER: X -- SOFT X-RAYS
Description : The mean free path of electrons in a metal is `4 xx 10^(-8)m` The electric field which can give on an average `2eV` energy to an electron in the metal
Last Answer : The mean free path of electrons in a metal is `4 xx 10^(-8)m` The electric field which can give on an average ... 11)` C. `8xx10^(-11)` D. `5xx10^(7)`
Description : (2) experience collision less frequently Explanation: When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that ... to free electrons. This means mobility is also less for a hole compared to free electron.
Last Answer : Carbon dioxide is called a greenhouse gas because - (1) its concentration remains always higher than other gases (2) it is used in photosynthesis (3) it absorbs infrared radiation (4) it emits visible radiation
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 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 : A space ship traveling toward Mars at 0.6 times the speed of light c shoots an ELECTRON beam at Mars. If the electrons travel at 0.6 c RELATIVE TO THE SPACE SHIP, at what speed do the electrons impact the surface of Mars? w) 0.6 c x) 0.88 c y) 1.2 c z) 1.34 c
Last Answer : ANSWER: X -- 0.88 c
Description : Find the minimum energy that a `gamma`-ray must have to give rise to an electron -positron pair. `{:("Mass of electron",= 0.00055 am u,),("Mass of pos
Last Answer : Find the minimum energy that a `gamma`-ray must have to give rise to an electron -positron pair. `{:("Mass ... ("Mass of positron",= 0.00055 am u,):}`
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 : A waveguide bend must have what minimum radius?
Last Answer : Greater than 2 wavelengths.
Description : Emergency eyewash facilities must be located within what minimum number of feet of an eyehazard area?
Last Answer : 10 feet.
Description : To radiate power efficiently, a long-wire antenna must have what minimum overall length?
Last Answer : One-half wavelength.
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 : 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 : 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 : For an electric field to exist at the surface of a conductor, the field must have what angular relationship to the conductor?
Last Answer : The field must be perpendicular to the conductors.
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 : 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 : 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
Description : In a Klystron amplifier, the RF voltage produces (a) amplitude modulation (b) frequency modulation (c) phase modulation (d) velocity modulation
Last Answer : In a Klystron amplifier, the RF voltage produces velocity modulation
Description : In a klystron amplifier the input cavity is called: (1) Buncher (2) Catcher (3) Pierce gun (4) Collector
Last Answer : In a klystron amplifier the input cavity is called: Buncher.