What is a beam antenna?
CAn antenna that concentrates signals in one direction
technician pool
Subelement T9 question review
All 23 official questions with the exact winning phrase marked.
Which of the following describes a type of antenna loading?
AElectrically lengthening by inserting inductors in radiating elements
How is the polarization of an antenna described?
BBy the orientation of the electric field
What is a disadvantage of a handheld radio transceiver’s short flexible antenna compared to a full-sized quarter-wave antenna?
AIt has low efficiency
Which of the following increases the resonant frequency of a dipole antenna?
CShortening it
Which of the following types of antennas offers the greatest gain?
DYagi
What is a potential drawback of using a handheld VHF transceiver inside a vehicle that lacks an externally mounted antenna?
ASignal strength is reduced due to the shielding effect of the vehicle
Why is a 19-inch-long vertical antenna often used on 2 meters?
CIt is a resonant quarter-wave
What is an advantage of a 5/8-wavelength whip antenna for VHF or UHF mobile service compared to a 1/4-wave antenna?
AIt has more gain
In which direction does a half-wave dipole antenna radiate the strongest signal?
DBroadside to the antenna
What is antenna gain?
CThe increase in signal strength in a specified direction compared to a reference antenna
Which of the following connectors should be carefully taped for weather protection when used outdoors?
DAll these choices are correct
What is the most common impedance of coaxial cables used in amateur radio?
B50 ohms
Why is coaxial cable the most common feed line for amateur radio antenna systems?
AIt is easy to use and requires few special installation considerations
What is the major function of an antenna tuner (antenna coupler)?
AIt matches the antenna system impedance to the transceiver's output impedance
What happens as the frequency of a signal in coaxial cable is increased?
DThe loss increases
Which of the following connector types is most suitable as an RF connector for frequencies above 400 MHz?
BType N
Which of the following is true of PL-259 type coax connectors?
CThey are commonly used at HF and VHF frequencies
Which of the following is a source of loss in coaxial feed line?
DAll these choices are correct
What can cause erratic changes in SWR?
BLoose connection in the antenna or feed line
What is the electrical difference between RG-58 and RG-213 coaxial cable?
CRG-213 cable has less loss at a given frequency
Which of the following types of feed line has the lowest loss?
CAir-insulated hardline
What is standing wave ratio (SWR)?
AA measure of how well a load is matched to a transmission line