Ham Radio General Class Test Amateur Radio Practices 4 — Questions and Answers
Question 1: Which of the following best describes the 'net control station' (NCS) role?
- The station with the strongest signal on the net frequency
- The station responsible for directing and maintaining orderly net operations (Correct answer)
- The station that provides the repeater for the net
- The station that logs all net contacts for the FCC
Correct answer: The station responsible for directing and maintaining orderly net operations
The net control station manages check-ins, directs traffic flow, and keeps the net running in an orderly manner.
Question 2: What is the advantage of using a digital mode such as FT8 compared to SSB voice during weak-signal conditions?
- FT8 uses more bandwidth, allowing stronger signals
- FT8 can decode signals many dB below what the human ear can hear in noise (Correct answer)
- FT8 allows keyboard-to-keyboard conversations in real time
- FT8 is the only mode legal for DX contacts
Correct answer: FT8 can decode signals many dB below what the human ear can hear in noise
FT8 uses forward error correction and computer decoding to pull signals out of noise at levels 15–20 dB below what SSB requires.
Question 3: What is 'pileup' in amateur radio DX operating?
- A malfunction causing multiple signals on one frequency
- Many stations simultaneously calling a rare DX station (Correct answer)
- When two stations talk over each other by accident
- An interference pattern caused by multipath propagation
Correct answer: Many stations simultaneously calling a rare DX station
A pileup occurs when a large number of stations all call a rare or sought-after DX station at the same time, creating a chaotic mix of signals.
Question 4: What is a 'repeater offset' and why is it needed?
- The time delay between input and output of a repeater
- The frequency difference between a repeater's receive and transmit frequencies (Correct answer)
- The power reduction a repeater applies to prevent interference
- The geographic distance between two linked repeaters
Correct answer: The frequency difference between a repeater's receive and transmit frequencies
A repeater receives on one frequency and transmits on another; the offset is the difference between these two, allowing full-duplex operation.
Question 5: What is the purpose of sending 'QRL?' before transmitting on an HF frequency?
- To request a signal report from nearby stations
- To ask if the frequency is in use before transmitting (Correct answer)
- To announce your call sign in abbreviated form
- To request that other stations stand by for a priority message
Correct answer: To ask if the frequency is in use before transmitting
QRL? is the Q-code query meaning 'Is this frequency in use?' — a courtesy check to avoid interfering with an ongoing contact.
Question 6: What does a high SWR reading on your feed line indicate?
- Your transmitter is operating at maximum efficiency
- There is an impedance mismatch between the feed line and the antenna (Correct answer)
- The antenna has excellent gain in all directions
- Your power output is too low to drive the antenna
Correct answer: There is an impedance mismatch between the feed line and the antenna
High SWR indicates that the antenna and feed line impedances are not matched, causing power to be reflected back toward the transmitter.
Question 7: What is 'picket fencing' as experienced on a VHF mobile station?
- Interference from nearby picket-fence-shaped antenna patterns
- Rapid flutter or pulsing in signal strength caused by multipath reflections while moving (Correct answer)
- A method of stacking Yagi antennas for added gain
- A digital framing error causing corrupted audio packets
Correct answer: Rapid flutter or pulsing in signal strength caused by multipath reflections while moving
Picket fencing is rapid, rhythmic signal fading caused by the mobile antenna alternately passing through constructive and destructive interference zones.
Ham Radio General Class Test Amateur Radio Practices 4
Which of the following best describes the 'net control station' (NCS) role?