Topic G4: Amateur Radio Practices
G4A-2011: Station Operation and setup
What is the purpose of the "notch filter" found on many HF transceivers?
To reduce interference from carriers in the receiver passband
To restrict the transmitter voice bandwidth
To eliminate receiver interference from impulse noise sources
To enhance the reception of a specific frequency on a crowded band
What is one advantage of selecting the opposite or "reverse" sideband when receiving CW signals on a typical HF transceiver?
It may be possible to reduce or eliminate interference from other signals
Interference from impulse noise will be eliminated
More stations can be accommodated within a given signal passband
Accidental out of band operation can be prevented
What is normally meant by operating a transceiver in "split" mode?
The transceiver is set to different transmit and receive frequencies
The radio is operating at half power
The transceiver is operating from an external power source
The transmitter is emitting a SSB signal, as opposed to DSB operation
What reading on the plate current meter of a vacuum tube RF power amplifier indicates correct adjustment of the plate tuning control?
A pronounced dip
A pronounced peak
No change will be observed
A slow, rhythmic oscillation
What is a purpose of using Automatic Level Control (ALC) with a RF power amplifier?
To reduce distortion due to excessive drive
To balance the transmitter audio frequency response
To reduce harmonic radiation
To increase overall efficiency
What type of device is often used to enable matching the transmitter output to an impedance other than 50 ohms?
What condition can lead to permanent damage when using a solid-state RF power amplifier?
Excessive drive power
Exceeding the Maximum Usable Frequency
Low input SWR
Shorting the input signal to ground
What is the correct adjustment for the load or coupling control of a vacuum tube RF power amplifier?
Maximum power output without exceeding maximum allowable plate current
Minimum SWR on the antenna
Minimum plate current without exceeding maximum allowable grid current
Highest plate voltage while minimizing grid current
Why is a time delay sometimes included in a transmitter keying circuit?
To allow time for transmit-receive changeover operations to complete properly before RF output is allowed
To prevent stations from talking over each other
To allow the transmitter power regulators to charge properly
To allow time for a warning signal to be sent to other stations
What is the purpose of an electronic keyer?
Automatic generation of strings of dots and dashes for CW operation
Automatic transmit/receive switching
Computer interface for PSK and RTTY operation
Which of the following is a use for the IF shift control on a receiver?
To avoid interference from stations very close to the receive frequency
To change frequency rapidly
To permit listening on a different frequency from that on which you are transmitting
To tune in stations that are slightly off frequency without changing your transmit frequency
Which of the following is a common use for the dual VFO feature on a transceiver?
To permit ease of monitoring the transmit and receive frequencies when they are not the same
To allow transmitting on two frequencies at once
To permit full duplex operation, that is transmitting and receiving at the same time
To facilitate computer interface
What is one reason to use the attenuator function that is present on many HF transceivers?
To reduce signal overload due to strong incoming signals
To reduce the transmitter power when driving a linear amplifier
To reduce power consumption when operating from batteries
To slow down received CW signals for better copy
How should the transceiver audio input be adjusted when transmitting PSK31 data signals?
So that the transceiver ALC system does not activate
So that the transceiver is at maximum rated output power
So that the transceiver operates at no more than 25% of rated power
So that the transceiver ALC indicator shows half scale
G4B-2011: Test and monitoring equipment; two-tone test
What item of test equipment contains horizontal and vertical channel amplifiers?
A signal generator
Which of the following is an advantage of an oscilloscope versus a digital voltmeter?
Complex waveforms can be measured
An oscilloscope uses less power
Complex impedances can be easily measured
Input impedance is much lower
Which of the following is the best instrument to use when checking the keying waveform of a CW transmitter?
A field-strength meter
A sidetone monitor
What signal source is connected to the vertical input of an oscilloscope when checking the RF envelope pattern of a transmitted signal?
The attenuated RF output of the transmitter
The local oscillator of the transmitter
An external RF oscillator
The transmitter balanced mixer output
Why is high input impedance desirable for a voltmeter?
It decreases the loading on circuits being measured
It improves the frequency response
It decreases battery consumption in the meter
It improves the resolution of the readings
What is an advantage of a digital voltmeter as compared to an analog voltmeter?
Better precision for most uses
Better for measuring computer circuits
Better for RF measurements
Which of the following might be a use for a field strength meter?
Close-in radio direction-finding
A modulation monitor for a frequency or phase modulation transmitter
An overmodulation indicator for a SSB transmitter
A keying indicator for a RTTY or packet transmitter
Which of the following instruments may be used to monitor relative RF output when making antenna and transmitter adjustments?
A field-strength meter
An antenna noise bridge
A Q meter
Which of the following can be determined with a field strength meter?
The radiation pattern of an antenna
The radiation resistance of an antenna
The presence and amount of phase distortion of a transmitter
The presence and amount of amplitude distortion of a transmitter
Which of the following can be determined with a directional wattmeter?
Standing wave ratio
Antenna front-to-back ratio
Radio wave propagation
Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
Antenna and feed line
All of these choices are correct
What problem can occur when making measurements on an antenna system with an antenna analyzer?
Strong signals from nearby transmitters can affect the accuracy of measurements
SWR readings may be incorrect if the antenna is too close to the Earth
The analyzer can be damaged if measurements outside the ham bands are attempted
Connecting the analyzer to an antenna can cause it to absorb harmonics
What is a use for an antenna analyzer other than measuring the SWR of an antenna system?
Determining the impedance of an unknown or unmarked coaxial cable
Measuring the front to back ratio of an antenna
Measuring the turns ratio of a power transformer
Determining the gain of a directional antenna
What is an instance in which the use of an instrument with analog readout may be preferred over an instrument with a numerical digital readout?
When adjusting tuned circuits
When testing logic circuits
When high precision is desired
When measuring the frequency of an oscillator
What type of transmitter performance does a two-tone test analyze?
Carrier and undesired sideband suppression
Percentage of frequency modulation
Percentage of carrier phase shift
What signals are used to conduct a two-tone test?
Two non-harmonically related audio signals
Two audio signals of the same frequency shifted 90-degrees
Two swept frequency tones
Two audio frequency range square wave signals of equal amplitude
G4C-2011: Interference with consumer electronics; grounding; DSP
Which of the following might be useful in reducing RF interference to audio-frequency devices?
Which of the following could be a cause of interference covering a wide range of frequencies?
Arcing at a poor electrical connection
Not using a balun or line isolator to feed balanced antennas
Lack of rectification of the transmitter's signal in power conductors
The use of horizontal rather than vertical antennas
What sound is heard from an audio device or telephone if there is interference from a nearby single-sideband phone transmitter?
A steady hum whenever the transmitter is on the air
On-and-off humming or clicking
Clearly audible speech
What is the effect on an audio device or telephone system if there is interference from a nearby CW transmitter?
On-and-off humming or clicking
A CW signal at a nearly pure audio frequency
A chirpy CW signal
Severely distorted audio
What might be the problem if you receive an RF burn when touching your equipment while transmitting on an HF band, assuming the equipment is connected to a ground rod?
The ground wire has high impedance on that frequency
Flat braid rather than round wire has been used for the ground wire
Insulated wire has been used for the ground wire
The ground rod is resonant
What effect can be caused by a resonant ground connection?
High RF voltages on the enclosures of station equipment
Overheating of ground straps
Corrosion of the ground rod
A ground loop
What is one good way to avoid unwanted effects of stray RF energy in an amateur station?
Connect all equipment grounds together
Install an RF filter in series with the ground wire
Use a ground loop for best conductivity
Install a few ferrite beads on the ground wire where it connects to your station
Which of the following would reduce RF interference caused by common-mode current on an audio cable?
Placing a ferrite bead around the cable
Adding series capacitors to the conductors
Adding shunt inductors to the conductors
Adding an additional insulating jacket to the cable
How can a ground loop be avoided?
Connect all ground conductors to a single point
Connect all ground conductors in series
Connect the AC neutral conductor to the ground wire
Avoid using lock washers and star washers when making ground connections
What could be a symptom of a ground loop somewhere in your station?
You receive reports of "hum" on your station's transmitted signal
The SWR reading for one or more antennas is suddenly very high
An item of station equipment starts to draw excessive amounts of current
You receive reports of harmonic interference from your station
Which of the following is one use for a Digital Signal Processor in an amateur station?
To remove noise from received signals
To provide adequate grounding
To increase antenna gain
To increase antenna bandwidth
Which of the following is an advantage of a receiver Digital Signal Processor IF filter as compared to an analog filter?
A wide range of filter bandwidths and shapes can be created
Fewer digital components are required
Mixing products are greatly reduced
The DSP filter is much more effective at VHF frequencies
Which of the following can perform automatic notching of interfering carriers?
A Digital Signal Processor (DSP) filter
A noise limiter
G4D-2011: Speech processors; S meters; sideband operation near band edges
What is the purpose of a speech processor as used in a modern transceiver?
Increase the intelligibility of transmitted phone signals during poor conditions
Increase transmitter bass response for more natural sounding SSB signals
Prevent distortion of voice signals
Decrease high-frequency voice output to prevent out of band operation
Which of the following describes how a speech processor affects a transmitted single sideband phone signal?
It increases average power
It increases peak power
It reduces harmonic distortion
It reduces intermodulation distortion
Which of the following can be the result of an incorrectly adjusted speech processor?
All of these choices are correct
Excessive background pickup
What does an S meter measure?
Received signal strength
Transmitter power output
How does an S meter reading of 20 dB over S-9 compare to an S-9 signal, assuming a properly calibrated S meter?
It is 100 times stronger
It is 10 times weaker
It is 20 times weaker
It is 20 times stronger
Where is an S meter found?
In a receiver
In an SWR bridge
In a transmitter
In a conductance bridge
How much must the power output of a transmitter be raised to change the S-meter reading on a distant receiver from S8 to S9?
Approximately 4 times
Approximately 1.5 times
Approximately 2 times
Approximately 8 times
What frequency range is occupied by a 3 kHz LSB signal when the displayed carrier frequency is set to 7.178 MHz?
7.175 to 7.178 MHz
7.178 to 7.181 MHz
7.178 to 7.184 MHz
7.1765 to 7.1795 MHz
What frequency range is occupied by a 3 kHz USB signal with the displayed carrier frequency set to 14.347 MHz?
14.347 to 14.350 MHz
14.347 to 14.647 MHz
14.344 to 14.347 MHz
14.3455 to 14.3485 MHz
How close to the lower edge of the 40 meter General Class phone segment should your displayed carrier frequency be when using 3 kHz wide LSB?
3 kHz above the edge of the segment
3 kHz below the edge of the segment
Your displayed carrier frequency may be set at the edge of the segment
Center your signal on the edge of the segment
How close to the upper edge of the 20 meter General Class band should your displayed carrier frequency be when using 3 kHz wide USB?
3 kHz below the edge of the band
3 kHz above the edge of the band
Your displayed carrier frequency may be set at the edge of the band
Center your signal on the edge of the band
G4E-2011: HF mobile radio installations; emergency and battery powered operation
What is a "capacitance hat", when referring to a mobile antenna?
A device to electrically lengthen a physically short antenna
A device to increase the power handling capacity of a mobile whip antenna
A device that allows automatic band-changing for a mobile antenna
A device that allows remote tuning of a mobile antenna
What is the purpose of a "corona ball" on a HF mobile antenna?
To reduce high voltage discharge from the tip of the antenna
To narrow the operating bandwidth of the antenna
To increase the "Q" of the antenna
To reduce the chance of damage if the antenna should strike an object
Which of the following direct, fused power connections would be the best for a 100-watt HF mobile installation?
To the battery using heavy gauge wire
To the alternator or generator using heavy gauge wire
To the battery using resistor wire
To the alternator or generator using resistor wire
Why is it best NOT to draw the DC power for a 100-watt HF transceiver from an automobile's auxiliary power socket?
The socket's wiring may be inadequate for the current being drawn by the transceiver
The socket is not wired with an RF-shielded power cable
The DC polarity of the socket is reversed from the polarity of modern HF transceivers
Drawing more than 50 watts from this socket could cause the engine to overheat
Which of the following most limits the effectiveness of an HF mobile transceiver operating in the 75 meter band?
The antenna system
“Picket Fencing” signal variation
The wire gauge of the DC power line to the transceiver
FCC rules limiting mobile output power on the 75 meter band
What is one disadvantage of using a shortened mobile antenna as opposed to a full size antenna?
Operating bandwidth may be very limited
Short antennas are more likely to cause distortion of transmitted signals
Short antennas can only receive vertically polarized signals
Harmonic radiation may increase
Which of the following is the most likely to cause interfering signals to be heard in the receiver of an HF mobile installation in a recent model vehicle?
The vehicle control computer
The battery charging system
The anti-lock braking system
The anti-theft circuitry
What is the name of the process by which sunlight is changed directly into electricity?
What is the approximate open-circuit voltage from a modern, well-illuminated photovoltaic cell?
What is the reason a series diode is connected between a solar panel and a storage battery that is being charged by the panel?
The diode prevents self discharge of the battery through the panel during times of low or no illumination
The diode serves to regulate the charging voltage to prevent overcharge
The diode limits the current flowing from the panel to a safe value
The diode greatly increases the efficiency during times of high illumination
Which of the following is a disadvantage of using wind as the primary source of power for an emergency station?
A large energy storage system is needed to supply power when the wind is not blowing
The conversion efficiency from mechanical energy to electrical energy is less than 2 percent
The voltage and current ratings of such systems are not compatible with amateur equipment
All of these choices are correct
● = Unseen
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● = Learned
● = Incorrect answer