All RF Cafe quizzes would make perfect fodder for employment interviews for technicians or engineers - particularly those who are fresh out
of school or are relatively new to the work world. Come to think of it, they would make equally excellent study material for the same persons
who are going to be interviewed for a job.
Some of these books used in quizzes are available as prizes in the monthly
RF Cafe Giveaway.
Note: Many answers contain passages quoted in whole or in part from the text.
1. What does dBi, the most
often used unit for antenna gain (or directivity), stand for?
a) Decibels of isolation
radiation in decibels
c) Decibels of gain relative to an isotropic radiator
d) Intrinsic gain in decibels
2. For which region of space does antenna gain normally apply?
a) Near field
b) Far field
the feed point
Elevation Pattern Azimuth Pattern
3. For which type of antenna does the pattern to the right describe?
d) 1/4-wave vertical whip
4. What is the free space impedance that an antenna "sees?"
a) 50 Ω
b) 75 Ω
c) 16p Ω (≈50 Ω)
d) 120p Ω (≈377 Ω)
5. What is the name given to the point where the RF input signal interfaces to the antenna?
(input connection point)
c) BNC connector
d) N connector
6. Where is the
approximate transition point between near field and far field?
a) λ / (2p)
7. What is an isotropic radiator?
a) An antenna that radiates equally in all directions
An antenna with equal dimensions
c) An antenna designed to broadcast in the troposphere
d) None of the above
8. Which type of antenna would typically have the highest directivity?
a) 1/4-wave whip
9. On a center-fed 1/2-wave dipole, where is the voltage
potential the highest?
a) In the center
b) At the tips
c) Equal everywhere
d) Nowhere - dipoles
operate on current
10. Yagi antennas are constructed of which three types of elements?
a) Transmitter, receiver,
b) Underdriven, driven, and overdriven
c) Reflector, driven, and director
iron, and magnesium
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