Description : Which of the following is not a bounded medium? A. Coaxial line B. Two-wire line C. Waveguide D. Free space
Last Answer : D. Free space
Description : . Why are coaxial lines more efficient at microwave frequencies than two-wire transmission lines?
Last Answer : The electromagnetic fields are completely confined
Description : What causes the current-carrying area at the center conductor of a coaxial line to be restricted to a small layer at the surface?
Last Answer : Skin effect.
Description : What is the most common type of waveguide joint?
Last Answer : Choke joint.
Description : What are the two types of coaxial lines in use today?
Last Answer : Air coaxial (rigid) and solid coaxial (flexible).
Description : A large numbers of computers in a wide geographical area can be efficiently connected using (A) twisted pair lines (B) coaxial cables (C) Communication satellites (D) all of the above
Last Answer : (D) all of the above
Description : How does a waveguide-type lens focus spherical wavefront microwave energy?
Last Answer : Some wavefronts are accelerated so that all wavefronts exit the lens at the same time
Description : Consider the following statements concerning food chains. A. Removal of 80% tigers from an area resulted in greatly increased growth of vegetation. B. Removal of most of the carnivores resulted in an increased population of deers. C. ... are correct? (a) A, D (b) A, B (c) B, C (d) C, D
Last Answer : (c) B, C
Description : In second generation computers, how was the storage capacity greatly increased?
Last Answer : With the introduction of magnetic disk storage and the use of
Description : Name the components which greatly increase the weight of vacuum-tube circuitry.
Last Answer : Transformers, capacitors, and resistors.
Description : When the frequency is decreased so that two quarter wavelengths are longer than the "a" (wide) dimension of the waveguide, what will happen?
Last Answer : Energy will no longer pass through the waveguide.
Description : What is the most likely cause of losses in waveguide systems?
Last Answer : Improperly connected joints or damaged inner surface.
Description : A waveguide bend must have what minimum radius?
Last Answer : Greater than 2 wavelengths.
Description : What is the result of an abrupt change in the size, shape, or dielectric of a waveguide?
Last Answer : Reflections.
Description : When a waveguide is terminated in a resistive load, the load must be matched to what property of the waveguide?
Last Answer : . Characteristic impedance.
Description : What device is used to produce a gradual change in impedance at the end of a waveguide?
Last Answer : Horn.
Description : What is the result of an impedance mismatch in a waveguide?
Last Answer : Standing waves that cause power losses, a reduction in power handling capability, and an increase in frequency and sensitivity.
Description : Loose or inefficient coupling of energy into or out of a waveguide can be accomplished by the use of what method?
Last Answer : Slots and apertures.
Description : What determines the frequency, bandwidth, and power handling capability of a waveguide probe?
Last Answer : Size and shape
Description : Which subscript, in circular waveguide classification, indicates the number of full-wave patterns around the circumference?
Last Answer : First.
Description : The electric field is perpendicular to the "a" dimension of a waveguide in what mode?
Last Answer : TE.
Description : How is the cutoff wavelength of a circular waveguide figured?
Last Answer : 1.71 times the diameter.
Description : What field configuration is easiest to produce in a given waveguide?
Last Answer : . Dominant mode
Description : What term is used to identify the forward progress velocity of wavefronts in a waveguide?
Last Answer : Group velocity.
Description : incidence and reflection that are perpendicular to the waveguide walls?
Last Answer : Cutoff frequency.
Description : Assuming the wall of a waveguide is perfectly flat, what is the angular relationship between the angle of incidence and the angle of reflection
Last Answer : The angles are equal.
Description : When a wavefront is radiated into a waveguide, what happens to the portions of the wavefront that do not satisfy the boundary conditions?
Last Answer : Decrease to zero.
Description : What interaction causes energy to travel down a waveguide?
Last Answer : The interaction of the electric and magnetic fields.
Description : What happens to the bus bar dimensions of the waveguide when the frequency is increased?
Last Answer : The bus bar becomes wider.
Description : The frequency range of a waveguide is determined by what dimensions?
Last Answer : . The "a" dimension.
Description : The folded waveguide in a bwo serves the same purpose as what component in a twt?
Last Answer : Helix.
Description : Which dispersion mechanism (material or waveguide) is a function of the size of the fiber's core relative to the wavelength of operation?
Last Answer : Waveguide dispersion.
Description : Motor controllers are seldom troubled by grounds because ________________. A. cabinet heaters always keep internal components dry B. special insulation is used on wire for vital circuits C. ... on controller panels greatly reduce vibration D. contactors and relays are mounted on nonconducting panels
Last Answer : Answer: D
Description : Compare between waveguide and two wire transmission line
Last Answer : waveguide and two wire transmission line
Description : What type of balun (balanced-to-unbalanced) is used in high frequency applications? A. Transformer type balun B. A specially configured coaxial transmission line C. A specially configured parallel-wire line D. A λ/2 transformer balun
Last Answer : B. A specially configured coaxial transmission line
Description : What precautions should you take when tying bundles containing coaxial cables?
Last Answer : Do not tie too tightly and use the proper type of tape.
Description : Is the attenuation of a coaxial cable independent of frequency?
Last Answer : No.
Description : What factor has the greatest effect on the physical size of a coaxial cable?
Last Answer : The dielectric constant of the insulating material.
Description : List the three disadvantages of the air coaxial line
Last Answer : Expensive to construct, must be kept dry, and high frequency losses limit the practical length of the line.
Description : What is the chief advantage of the air coaxial line?
Last Answer : The ability to minimize radiation losses.
Description : Which of the following is considered the most frequently used transmission line? A. Two-wire open line B. Twin lead C. Rigid coaxial line D. Flexible coaxial line
Last Answer : D. Flexible coaxial line
Description : A transmission line consisting of two conductors that have equal resistance per unit length. A. Unbalanced line B. Open-wire line C. Balanced line D. Coaxial line
Last Answer : C. Balanced line
Description : What medium is used by IBM token ring network that operates at either 4 Mbps or 16 Mbps? A. Twisted pair B. Coaxial cable C. Fiber-optic D. Parallel-wire line
Last Answer : A. Twisted pair
Description : What line has a typical velocity factor of about 0.8? A. Shielded pair B. Flexible coaxial C. Twin-lead D. Open-wire line
Last Answer : C. Twin-lead
Description : Best choice of transmission line component to couple a coaxial line to a parallel-wire line A. Shorting B. Balun C. Slotted line D. Directional coupler
Last Answer : B. Balun
Description : To connect coaxial line to a parallel-wire _________ is the best to use. A. directional coupler B. quarter-wave transformer C. balun D. slotted line
Last Answer : C. balun
Description : The slowest transmissionspeeds are those of A. twisted-pair wire B. coaxial cable C. fiber-optic cable D. microwaves
Last Answer : twisted-pair wire
Description : Which of this is not a guided media? a) Fiber optical cable b) Coaxial cable c) Wireless LAN d) Copper wire
Last Answer : c) Wireless LAN
Description : Identify the odd term amongst the following group : (1) Optical fibre (2) Twisted pair wire (3) Microwaves (4) Coaxial cable
Last Answer : Microwaves
Description : To couple a coaxial line to a parallel wire line, it is best to use a: (1) A slotted line (2) Balun (3) Directional coupler (4) Quarter wave line transformer
Last Answer : To couple a coaxial line to a parallel wire line, it is best to use a: Balun.