Ham Radio Technician Test Antennas & Feedlines 4

Question 1

What is the effect of operating an antenna significantly off its resonant frequency without a tuner?

Accepted Answer

High SWR and increased feedline loss

Answer

Lower noise floor on receive

Answer

Increased antenna gain

Answer

The transceiver automatically adjusts power

Question 2

For a vertical antenna mounted on a vehicle rooftop, the car body serves as:

Accepted Answer

The ground plane

Answer

A director element

Answer

A noise shield

Answer

A loading coil

Question 3

What does antenna 'gain' mean in practical terms?

Accepted Answer

Concentrating radiated power in a preferred direction compared to a reference antenna

Answer

Amplifying the signal inside the antenna element

Answer

Increasing total radiated power beyond the transmitter output

Answer

Reducing the feedline loss

Question 4

Which connector type is commonly used with RG-8 or RG-213 coax for HF amateur radio?

Accepted Answer

PL-259 (UHF connector)

Answer

SMA

Answer

N-type

Answer

F-type

Question 5

What is a J-pole antenna?

Accepted Answer

A half-wave radiator fed at the base via a quarter-wave matching stub

Answer

A dipole bent into a J shape to reduce wind loading

Answer

A vertical antenna with a J-shaped ground radial

Answer

A type of loop antenna for 40 meters

Question 6

What is 'coax velocity factor' and why does it matter?

Accepted Answer

The speed of the signal in coax relative to free space; affects electrical length calculations

Answer

The rate at which coax heats under high power

Answer

The frequency at which coax becomes lossy

Answer

The ratio of coax impedance to antenna impedance

Question 7

What is the approximate free-space wavelength at 146 MHz?

Accepted Answer

About 2 meters (6.6 feet)

Answer

About 10 meters (33 feet)

Answer

About 70 centimeters (2.3 feet)

Answer

About 20 meters (65 feet)