Online Questions and Answers Topic Outline
- MCQs in Transmission System
- MCQs in Transmission Medium
- MCQs in Velocity and Line Wavelength
- MCQs in Characteristics Impedance
- MCQs in Primary Line Constants and Propagation Constants
- MCQs in Standing Waves
- MCQs in Voltage Standing Wave Ratio
- MCQs in Telephone Lines and Cables
- MCQs in Wave Guides
- MCQs in Balanced and Unbalanced Lines
- MCQs in Twisted pair wire, Coaxial Cable
- MCQs in Decibel
- MCQs in Signal and Noise Fundamentals
MCQs in Transmission Fundamentals Series
Following is the list of multiple choice questions in this brand new series:
Continue Practice Exam Test Questions Part IX of the Series
401. A (75 - j50)-ohm is connected to a coaxial transmission line of Zo = 75 ohms, at 10 GHz. The best method of matching consists of connecting
- A. A short-circuited stub at the load
- B. An inductive at the load
- C. A capacitance at some specific distance from the load
- D. A short-circuited stub at some specific distance from the load
402. The velocity factor of a transmission line
- A. Depends on the dielectric constant of the material used
- B. Increases in velocity along the transmission line
- C. Is governed by the skin effect
- D. Is higher for a solid dielectric than for air.
403. Impedance inversion may be obtained with
- A. A short-circuited stub
- B. An open-circuited stub
- C. A quarter-wave line
- D. A half-wave line
404. The most desirable reflection coefficient is
- A. 0
- B. 0.5
- C. 1
- D. Infinity
405. Short circuited stubs are preferred to open-circuited stub because the latter are
- A. More difficult to make and connect
- B. Made of a transmission line with different characteristic impedance
- C. Liable to radiate
- D. Incapable of giving a full range of reactance
406. For transmission-line load matching over a range of frequencies, it is best to use a
- A. Balun
- B. Broadband directional coupler
- C. Double stub
- D. Single stub of adjustable position
407. The main disadvantage of the two-hole directional coupler is
- A. Low directional coupling
- B. Poor directivity
- C. High SWR
- D. Narrow bandwidth
408. To couple a coaxial line to a parallel-wire line, it is best to use a
- A. Slotted line
- B. Balun
- C. Directional coupler
- D. Quarter-wave transformer
409. A short-circuited quarter-wavelength line acts like a
- A. Parallel resonant circuit
- B. Series resonant circuit
- C. Oscillator
- D. LC circuit
410. If the length of a short-circuited stub is less than a quarter-wavelength but greater than 0, the stub behaves as
- A. Inductor
- B. Capacitor
- C. Resistor
- D. Complex
411. The depth of penetration of current density resulting from skin effect
- A. Skin depth
- B. Wire depth
- C. Line depth
- D. Medium depth
412. Transmission line must be matched to the load to
- A. Transfer maximum voltage to the load
- B. Transfer maximum current to the load
- C. Reduce the load current
- D. Transfer maximum power to the load
413. Referred to the dielectric constant of a transmission line material
- A. Inductance and capacitance
- B. Velocity factor
- C. Characteristic impedance
- D. Propagation velocity
414. A transmission line containing of two conductors that have equal resistance per unit length
- A. Unbalanced line
- B. Open-wire line
- C. Balanced line
- D. Coaxial cable
415. Which of the following determines the characteristics of a transmission line?
- A. Inductance
- B. Capacitance
- C. Physical dimension
- D. Length
416. Category of UTP that was designed for data transmission rates up to 20 Mbps
- A. Category 5e
- B. Category 4
- C. Category 5
- D. Category 3
417. Level 2 or category 2 UTP cables comply with IBM’s _______ specification.
- A. Type 1
- B. Type 3
- C. Type 2
- D. Type 4
418. Level 3 or Category 3 UTP cables should have at least ____ twist per inch.
- A. 1
- B. 2
- C. 3
- D. 4
419. Which of the following is NOT a color code for Category 5 UTP?
- A. Blue/white stripe and blue
- B. Orange/white stripe and orange
- C. Red/white stripe and red
- D. Brown/white stripe and brown
420. Shielded-screen twisted-pair cable or SSTP is also known as ________.
- A. Cat 5e
- B. Cat 7
- C. Cat 6
- D. Cat 8
421. An open-circuited transmission line quarter wavelength long is equivalent to
- A. Parallel resonant circuit
- B. Series resonant circuit
- C. Inductive
- D. Capacitive
422. A short-circuited transmission line more than quarter-wavelength long but shorter than half wavelength is equivalent to _______.
- A. Series resonant circuit
- B. Inductive
- C. Capacitive
- D. Parallel resonant circuit
423. A short-circuited transmission line less than quarter-wavelength long.
- A. Inductive
- B. Capacitive
- C. Parallel resonant circuit
- D. Series resonant circuit
424. The quarter-wavelength transformer line acts as a transformer with a 1:1 turns ratio when the load resistance is with what relationship with the characteristic impedance of the quarter-wavelength transformer?
- A. Equal
- B. Less than
- C. Greater than
- D. None of these
425. The characteristic impedance of a microstrip is equal to _____ ohms.
- A. 50 to 200
- B. 25 to 50
- C. 100 to 200
- D. 50 to 75
426. The quarter-wavelength transformer line acts as a step down transformer when the load resistance is with what relationship with the characteristic impedance of the quarter-wavelength transformer?
- A. Equal
- B. Less than
- C. Greater than
- D. None of these
427. The typical value of the velocity factor of an open-wire transmission line is
- A. 0.8
- B. 0.7
- C. 0.6
- D. 0.9
428. If a transmission line is not terminated in its characteristic impedance, _______ will develop along the line.
- A. Traveling waves
- B. Standing waves
- C. Surge impedance
- D. Infinite impedance
429. If a load and a line have mismatched impedances, power not absorbed by the load will be _____.
- A. Absorbed
- B. Rejected
- C. Reflected
- D. Removed
430. Two wire line is usually operated in the:
- a. Balanced mode
- b. Unbalanced mode
- c. High frequency
- d. None of these
431. When the load impedance doesn’t not match the line impedance, part of the energy in the incident wave is ________ at the load.
- a. Forwarded
- b. Reflected
- c. Same
- d. None of these
432. In practice, the transmission lines are almost connected to antennas that have a _____.
- a. Resistive load whose resistance is greater than the characteristic impedance of the line
- b. Resistive load whose resistance is less than the characteristic impedance of the line
- c. Resistive load at the resonant frequency
- d. Capacitive load
433. When the transmission line is matched to the load, it
- a. Transfers maximum current to the load
- b. Transfers maximum voltage to the load
- c. Transfers maximum power to the load
- d. Reduces the load current
434. Conventional transmission media include
- a. Twisted cable pair
- b. Waveguide
- c. Fiber optic cable
- d. All of these
435. To couple a coaxial line to a parallel wire line, it is best to use a _____
- a. Slotted line
- b. Directional coupler
- c. Balun
- d. All of these
436. Impedance inversion may be obtained with
- a. An open circuited stub
- b. A short circuited stub
- c. A quarterwave line
- d. A half-wave line
437. To be properly matched, the ratio of maximum to minimum voltage along a transmission line should be equal to
- a. 50
- b. 10
- c. 2
- d. 1
438. When ZL ≠ Zo, the power sent down the line toward the load is called the
- a. The incident power
- b. The reflected power
- c. The power dissipation
- d. The carrier power
439. For transmission line load matching over a range of frequencies, it is best to use a
- a. Balun
- b. Broadband directional coupler
- c. Double stub
- d. Single adjustable stub
440. A short section of a transmission line, open or shorted that is used to match the impedance of the line to that of an antenna or transmitter.
- a. Slotted line
- b. Stub
- c. Wavetrap
- d. Lecher wire
441. The property of a material that determines how much electrostatic energy can be stored per unit volume when voltage is applied
- a. Permeability
- b. Magnetic effect
- c. Capacitance
- d. Permittivity
442. The value of the total opposition of the transmission media to the flow of electromagnetic field energy is called
- a. Characteristic impedance
- b. Velocity factor
- c. Standing waves
- d. Reflected waves
443. When mismatch is great, this power actually cause damage to the transmitter or the line itself.
- a. The incident power
- b. The reflected power
- c. The power dissipation
- d. The carrier power
444. What is the velocity factor for non-foam dielectric 50 or 75 ohm flexile coaxial cable such as RG 8, 11, 58 and 59?
- a. 270
- b. 0.10
- c. 0.66
- d. 0.30
445. The measure of the superiority of a material over a vacuum as a path for magnetic lines of force is
- a. Permittivity
- b. Permeability
- c. Conductivity
- d. Resistivity
446. The number of standing waves on the wire is equal to the length of the wire divided by a half wavelength. The principle which allows antennas to operate at different frequencies which are integral multiples of the fundamental frequency is called_______.
- a. Harmonic operation
- b. Decimonic operation
- c. Electromagnetic reverberation
- d. Asynchronous operation
447. A coax line has an attenuation of 2.4 dB per 100 ft. the attenuation for 2.75 ft. is _____ dB.
- a. 2.4
- b. 4.8
- c. 3.3
- d. 6.6
448. When a quarter wave stub is used to match a 600 ohm antenna to a line of 52 ohms, the impedance of the matching stub must be ____ ohms.
- a. 176
- b. 200
- c. 150
- d. 300
449. The characteristic impedance of a transmission line is determined by
- a. Its length
- b. Its height above ground
- c. Its physical construction
- d. The operating frequency
450. When the diameter of two conductors of a two-wire transmission line is held constant, the effect of decreasing the distance between the conductors is to
- a. Decrease the impedance
- b. Increase the surge impedance
- c. Increase the radiation resistance
- d. Decrease SWR
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