Free Ham Radio General Class MCQ Questions and Answers — Questions and Answers
Question 1: What may a ground loop in your station's audio connections manifest as?
- An item of station equipment starts to draw excessive amounts of current
- You receive reports of harmonic interference from your station
- The SWR reading for one or more antennas is suddenly very high
- You receive reports of “hum” on your station’s transmitted signal (Correct answer)
Correct answer: You receive reports of “hum” on your station’s transmitted signal
When people report hearing a "hum" in your station's transmitted signal, a ground loop may be the cause. Ground loops frequently cause interference and noise, and in rare situations, they could even put users at danger for electric shock.
Question 2: When utilizing 3 kHz wide LSB, how near to the lower edge of a band's phone segment should your displayed carrier frequency be?
- At least 1 kHz below the edge of the segment
- At least 1 kHz above the edge of the segment
- At least 3 kHz above the edge of the segment (Correct answer)
- At least 3 kHz below the edge of the segment
Correct answer: At least 3 kHz above the edge of the segment
When using 3 kHz wide LSB, your displayed carrier frequency must be at least 3 kHz higher than the lower edge of a band's phone section.
Question 3: Why should a storage battery that is being charged by a solar panel have a series diode connected between them?
- To prevent damage to the battery due to excessive voltage at high illumination levels
- To prevent overload by regulating the charging voltage
- To prevent discharge of the battery through the panel during times of low or no illumination (Correct answer)
- To limit the current flowing from the panel to a safe value
Correct answer: To prevent discharge of the battery through the panel during times of low or no illumination
To prevent discharge of the storage battery through the solar panel during periods of low or no light, a series diode is attached between the solar panel and the battery. Electronic parts with two terminals called diodes provide zero resistance in one direction and negligible resistance in the other.
Question 4: Which of the following tools can be applied to radio frequency impedance matching?
- A length of transmission line
- A transformer
- A Pi-network
- All of the above (Correct answer)
Correct answer: All of the above
Impedance matching at radio frequencies can be achieved using a transformer, a Pi-network, or a transmission line.
Question 5: What percentage of power is lost when 1 dB is lost?
- 25.9 percent
- 20.6 percent (Correct answer)
- 12.2 percent
- 10.9 percent
Correct answer: 20.6 percent
A power loss of 20.5% results from a line loss of 1 dB.
Question 6: What is the inductance of three parallel-connected 10-millihenry inductors?
- 30 millihenries
- 3.3 millihenries (Correct answer)
- 3.3 henries
- 0.30 henries
Correct answer: 3.3 millihenries
Three 10-millihenry inductors connected in parallel would have an inductance of 3.3 millihenries. The sum of one divided by each of the separate inductances equals one divided by the overall inductance.
Question 7: What vacuum tube component controls the passage of electrons between the cathode and the plate?
- Screen grid
- Trigger electrode
- Control grid (Correct answer)
- Suppressor grid
Correct answer: Control grid
The flow of electrons between the cathode and the plate of a vacuum tube is controlled by the control grid.
Free Ham Radio General Class MCQ Questions and Answers
What may a ground loop in your station's audio connections manifest as?