Free Ham Radio Technician General Questions and Answers — Questions and Answers

Question 1: When transmitting AFSK signals via a radio in single sideband mode, what is likely to happen if the ALC system on the transceiver is not properly configured?

Improper action of ALC distorts the signal and can cause spurious emissions (Correct answer)
All these choices are correct
ALC will invert the modulation of the AFSK mode
When using digital modes, too much ALC activity can cause the transmitter to overheat

Correct answer: Improper action of ALC distorts the signal and can cause spurious emissions

Explanation: This statement is partially correct. ALC (Automatic Level Control) is a system in a transceiver that automatically adjusts the gain of the transmitted signal to maintain a constant output power. When transmitting AFSK (Audio Frequency-Shift Keying) signals using single sideband mode, the ALC system needs to be set properly to prevent distortion and spurious emissions. If the ALC system is not set properly, it may result in overdriving the transmitter's power amplifier, causing distortion and spurious emissions that can interfere with other radio signals in the vicinity. Additionally, improper ALC setting can cause the transmitted signal to be too weak or too strong, leading to poor signal quality and potentially disrupting communications.

Question 2: What should you do as soon as you hear a difficult station break in while conversing with another amateur station?

Change to a different frequency
Acknowledge the station in distress and determine what assistance may be needed (Correct answer)
Continue your communication because you were on the frequency first
Immediately cease all transmissions

Correct answer: Acknowledge the station in distress and determine what assistance may be needed

Explanation: When communicating with another amateur station and hear a station in distress break in, the first thing you should do is to acknowledge the station in distress and determine what assistance may be needed. It's important to remain calm and professional in such situations and follow established emergency protocols.

Question 3: How does the receiving station react to an error-filled packet in ARQ data mode?

It requests the packet be retransmitted (Correct answer)
It requests a change in transmitting protocol
It sends the packet back to the transmitting station
It terminates the contact

Correct answer: It requests the packet be retransmitted

Explanation: When a receiving station receives an ARQ (Automatic Repeat Request) data mode packet containing errors, it sends a request for the packet to be retransmitted. This is because ARQ is a protocol used to ensure error-free data transmission over a noisy channel, and it uses acknowledgements and retransmissions to achieve this goal. When the receiving station detects errors in a packet, it sends a negative acknowledgement (NACK) to the transmitting station, which then retransmits the packet until it is received without errors or the maximum number of retransmission attempts is reached.

Question 4: When memory is described as non-volatile, what does that mean?

The stored information cannot be changed once written
It is resistant to high temperatures
It is resistant to radiation damage
The stored information is maintained even if power is removed (Correct answer)

Correct answer: The stored information is maintained even if power is removed

Explanation: Non-volatile memory is a type of computer memory that can retain stored information even when not powered, unlike volatile memory which requires a power source to retain data. Examples of non-volatile memory include ROM, flash memory, and hard disk drives.

Question 5: How is an RF power amplifier's effectiveness assessed?

Multiply the RF input power by the reciprocal of the RF output power
Add the RF input power to the DC output power
Divide the RF output power by the DC input power (Correct answer)
Divide the DC input power by the DC output power

Correct answer: Divide the RF output power by the DC input power

Explanation: The efficiency of an RF power amplifier is determined by dividing the RF output power by the total DC input power. This includes both the power consumed by the amplifier itself and any power lost due to inefficiencies in the power supply or other components. Efficiency is an important consideration in designing power amplifiers, as high efficiency allows more of the input power to be converted into useful RF output power, reducing wasted power and improving overall system performance.

Question 6: Which of the following best sums up a MOSFET's design?

The gate is separated from the channel with a thin insulating layer (Correct answer)
The source is separated from the drain by a thin insulating layer
The gate is formed by a back-biased junction
The source is formed by depositing metal on silicon

Correct answer: The gate is separated from the channel with a thin insulating layer

Explanation: The construction of a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) involves a gate electrode that is separated from the channel region by a thin insulating layer, typically made of silicon dioxide (SiO2). When a voltage is applied to the gate, an electric field is created that controls the flow of current through the channel.

Question 7: What is a property of skywave signals traveling both short and long paths to reach your location?

Periodic fading approximately every 10 seconds
A slightly delayed echo might be heard (Correct answer)
The signal might be cancelled causing severe attenuation
Signal strength increased by 3 dB

Correct answer: A slightly delayed echo might be heard

Explanation: When a skywave signal arrives at a location via both short-path and long-path propagation, a slightly delayed echo may be heard. This is because the signal bounces off the ionosphere and arrives at the receiving station by both paths, with the long-path signal taking a longer route and arriving slightly later.

Question 8: What qualifies as a QPSK31 characteristic?

Its bandwidth is approximately the same as BPSK31
Its encoding provides error correction
It is sideband sensitive
All these choices are correct (Correct answer)

Correct answer: All these choices are correct

QPSK31 (Quadrature Phase-Shift Keying 31) is a digital modulation mode used in amateur radio communications and other applications.

Question 9: What safety measures must to be taken before installing an interior transmitting antenna?

Make sure that MPE limits are not exceeded in occupied areas (Correct answer)
Make sure the antenna is properly shielded
Locate the antenna close to your operating position to minimize feed line radiation
Position the antenna the edge of a wall to reduce parasitic radiation

Correct answer: Make sure that MPE limits are not exceeded in occupied areas

Before installing an interior transmitting antenna, several safety measures must be taken to ensure the safety of occupants and comply with regulations. One crucial safety measure is to make sure that Maximum Permissible Exposure (MPE) limits are not exceeded in occupied areas.

Question 10: Between what two frequencies is a band-pass filter's bandwidth measured?

Cutoff and rolloff
Image and harmonic
Pole and zero
Upper and lower half-power (Correct answer)

Correct answer: Upper and lower half-power

A band-pass filter's bandwidth is typically measured between the upper and lower half-power frequencies. The upper half-power frequency is the frequency at which the filter's output power has decreased to half (-3 dB) of its maximum passband power. Similarly, the lower half-power frequency is the frequency at which the output power has decreased to half (-3 dB) of its maximum passband power.

Question 11: What is the combined resistance of a parallel connection of a 10 ohm, a 20 ohm, and a 50 ohm resistor?

10000 ohms
80 ohms
0.17 ohms
5.9 ohms (Correct answer)

Correct answer: 5.9 ohms

For resistors in parallel, 1/R_total = 1/10 + 1/20 + 1/50 = 0.17, so R_total ≈ 5.9 ohms. Parallel combinations always yield a total resistance lower than the smallest resistor (10 ohms here), which rules out 80 ohms and 10000 ohms, while 0.17 ohms is the reciprocal sum mistaken for the answer rather than its inverse.

Question 12: Why does radio wave propagation over the greatest distance primarily occur in the F2 region?

Because of meteor trails at that level
Because it is the highest ionospheric region (Correct answer)
Because it is the densest ionospheric layer
Because of the Doppler effect

Correct answer: Because it is the highest ionospheric region

Radio wave propagation over the greatest distance primarily occurs in the F2 region of the ionosphere because it is the highest and most important ionospheric layer for long-distance radio communications. The F2 region, also known as the F layer, is located at the highest altitudes within the ionosphere, extending approximately from 200 to 600 km (125 to 375 miles) above the Earth's surface.

Question 13: How is a Frequency Shift Keyed (FSK) signal's two distinct frequencies identified?

On and off
High and low
Mark and space (Correct answer)
Dot and dash

Correct answer: Mark and space

FSK is a digital modulation technique used in telecommunications and data transmission, where digital information is represented by alternating between two different frequencies. These frequencies are commonly referred to as the mark and space frequencies.

Question 14: Which of the following qualifications must someone possess in order to administer VE for a Technician class licensure exam?

Possession of a properly obtained telegraphy license
Notification to the FCC that you want to give an examination
An FCC General class or higher license and VEC accreditation (Correct answer)
Receipt of a Certificate of Successful Completion of Examination (CSCE) for General class

Correct answer: An FCC General class or higher license and VEC accreditation

To administer a Technician class exam, a Volunteer Examiner must hold an FCC General class license or higher and be accredited by a Volunteer Examiner Coordinator (VEC). A telegraphy license, merely notifying the FCC, or holding a CSCE for General does not grant VE authority — accreditation through a VEC is required.

Question 15: What justifies neutralizing a transmitter's last amplifier stage?

To limit the modulation index
To keep the carrier on frequency
To cut off the final amplifier during standby periods
To eliminate self-oscillations (Correct answer)

Correct answer: To eliminate self-oscillations

Neutralizing a transmitter's last amplifier stage is done to eliminate self-oscillations that may occur within the amplifier. When a transmitter operates at high power levels, it can generate strong RF (radio frequency) signals that may leak back into the amplifier's input circuits. This feedback can cause the amplifier to self-oscillate, meaning it starts to generate unwanted RF signals at its output, even without an input signal. Self-oscillations can lead to interference with other nearby electronic devices, distortion of the transmitted signal, and potential damage to the amplifier itself.

Question 16: How much power is lost when 7.0 milliamperes of current travel through a 1250 ohm resistance?

Approximately 11 milliwatts
Approximately 11 watts
Approximately 61 milliwatts (Correct answer)
Approximately 61 watts

Correct answer: Approximately 61 milliwatts

Power dissipated in a resistor is P = I²R, so (0.007 A)² × 1250 Ω = 0.000049 × 1250 ≈ 0.061 W, or about 61 milliwatts. The answers in watts are off by a factor of 1000 (a unit error), and 11 mW comes from miscalculating the squared current.

Free Ham Radio Technician General Questions and Answers

When transmitting AFSK signals via a radio in single sideband mode, what is likely to happen if the ALC system on the transceiver is not properly configured?