Ham Radio Technician Test Equipment & Tools Usage 5

Question 1

What test equipment would you use to verify that a newly built low-pass filter is suppressing harmonics above 30 MHz?

Accepted Answer

Spectrum analyzer with a tracking generator or a network analyzer

Answer

Multimeter set to AC voltage

Answer

SWR meter only

Answer

Frequency counter

Question 2

Why is it important to ground the outer shield of a coaxial cable at the point where it enters a building?

Accepted Answer

To protect against lightning-induced surges and reduce RF interference entering the shack

Answer

To increase cable bandwidth

Answer

To raise the impedance to 75 ohms

Answer

To prevent the cable from picking up audio frequencies

Question 3

What is the function of a bias-T in an antenna system?

Accepted Answer

It allows DC power to be fed through a coaxial cable to power remote devices such as preamps

Answer

It matches a 75-ohm feedline to a 50-ohm radio

Answer

It converts single-ended coax to a balanced line

Answer

It prevents standing waves on the feedline

Question 4

An operator notices their received audio has a 60 Hz hum. Which of the following is the most likely cause?

Accepted Answer

A ground loop or inadequate filtering in the power supply is coupling AC hum into the audio chain

Answer

The transmitter is running at excessive power

Answer

The antenna SWR is above 3:1

Answer

The squelch is set too low

Question 5

What is the purpose of ferrite beads or a common-mode choke on a feedline near the transmitter?

Accepted Answer

To suppress common-mode RF current flowing on the outside of the coax shield

Answer

To tune the antenna to resonance

Answer

To reduce the DC resistance of the feedline

Answer

To increase the SWR bandwidth

Question 6

When installing a mobile VHF/UHF antenna on a vehicle, what is the purpose of making a good DC ground connection to the vehicle chassis?

Accepted Answer

To provide an RF ground plane that improves antenna performance and reduces noise

Answer

To supply operating voltage to the radio

Answer

To prevent the antenna from vibrating at highway speeds

Answer

To meet FCC Part 95 requirements

Question 7

What tool is used to properly install BNC and N-type crimp connectors onto coaxial cable?

Accepted Answer

A coaxial crimp tool matched to the connector size

Answer

Needle-nose pliers

Answer

A calibrated torque wrench

Answer

A soldering iron alone