Ham Radio General Class Test Amateur Radio Practices 3 — Questions and Answers
Question 1: What is the purpose of the RIT (Receiver Incremental Tuning) control on a transceiver?
- To adjust transmit frequency independently of receive frequency
- To adjust receive frequency independently of transmit frequency (Correct answer)
- To increase receiver sensitivity
- To tune the antenna without affecting the receiver
Correct answer: To adjust receive frequency independently of transmit frequency
RIT allows you to shift the receive frequency slightly without moving the transmit frequency, useful when the other station is slightly off frequency.
Question 2: What is a 'gray line' and why is it significant to HF operators?
- A noise region near powerlines that degrades HF signals
- The terminator between day and night where propagation is often enhanced (Correct answer)
- A line on a band plan separating phone and CW segments
- The boundary between continental US and international waters for licensing
Correct answer: The terminator between day and night where propagation is often enhanced
The gray line is the transition zone between day and night; the ionosphere behaves unusually there, often producing excellent long-distance propagation.
Question 3: What is meant by 'full break-in' (QSK) CW operation?
- Transmitting CW at maximum legal power
- The ability to receive signals between individual dots and dashes while transmitting (Correct answer)
- Breaking into an ongoing CW contact
- Using a keyer that automatically spaces dots and dashes
Correct answer: The ability to receive signals between individual dots and dashes while transmitting
QSK (full break-in) allows you to hear other signals in the gaps between CW characters, enabling instant detection of interference or an emergency call.
Question 4: When must an amateur station identify itself during a QSO?
- Only at the beginning of each contact
- Only at the end of each contact
- At the end of each transmission and at least every 10 minutes (Correct answer)
- At the beginning, middle, and end of each contact
Correct answer: At the end of each transmission and at least every 10 minutes
FCC Part 97 requires station identification at the end of each transmission and at least every 10 minutes during a contact.
Question 5: What is the function of an 'automatic level control' (ALC) circuit in a transmitter?
- To automatically select the best operating frequency
- To prevent overdriving the final amplifier by reducing drive on strong audio peaks (Correct answer)
- To control the audio level of the received signal
- To balance the two sidebands in an SSB signal
Correct answer: To prevent overdriving the final amplifier by reducing drive on strong audio peaks
ALC feeds back a control voltage to reduce driver gain when audio peaks threaten to overdrive the PA, preventing distortion and splatter.
Question 6: What type of emission is produced by a transmitter that is being overmodulated?
- A cleaner, more efficient signal
- Splatter, which causes interference on adjacent frequencies (Correct answer)
- A reduced carrier level
- A signal confined entirely within the assigned bandwidth
Correct answer: Splatter, which causes interference on adjacent frequencies
Overmodulation causes the signal to 'splatter' — spreading energy beyond the intended bandwidth and interfering with adjacent channels.
Question 7: What is the purpose of a 'balun' at a dipole antenna feed point?
- To match a 300-ohm line to a 50-ohm radio
- To prevent RF current from flowing on the outside of the coaxial feed line (Correct answer)
- To increase the antenna's gain by 3 dB
- To protect the antenna against lightning strikes
Correct answer: To prevent RF current from flowing on the outside of the coaxial feed line
A balun (balanced-to-unbalanced) chokes off common-mode current on the coax shield, preventing the feed line from acting as part of the antenna.
Ham Radio General Class Test Amateur Radio Practices 3
What is the purpose of the RIT (Receiver Incremental Tuning) control on a transceiver?