G4 - AMATEUR RADIO PRACTICES [5 Exam Questions - 5 groups] Flashcards
What is the purpose of the “notch filter” found on many HF transceivers?
A. To restrict the transmitter voice bandwidth
B. To reduce interference from carriers in the receiver passband
C. To eliminate receiver interference from impulse noise sources
D. To enhance the reception of a specific frequency on a crowded band
B. To reduce interference from carriers in the receiver passband
What is one advantage of selecting the opposite or “reverse” sideband when receiving CW signals on a typical HF transceiver?
A. Interference from impulse noise will be eliminated
B. More stations can be accommodated within a given signal passband
C. It may be possible to reduce or eliminate interference from other signals
D. Accidental out of band operation can be prevented
C. It may be possible to reduce or eliminate interference from other signals
What is normally meant by operating a transceiver in “split” mode?
A. The radio is operating at half power
B. The transceiver is operating from an external power source
C. The transceiver is set to different transmit and receive frequencies
D. The transmitter is emitting a SSB signal, as opposed to DSB operation
C. The transceiver is set to different transmit and receive frequencies
What reading on the plate current meter of a vacuum tube RF power amplifier indicates correct adjustment of the plate tuning control?
A. A pronounced peak
B. A pronounced dip
C. No change will be observed
D. A slow, rhythmic oscillation
B. A pronounced dip
What is a purpose of using Automatic Level Control (ALC) with a RF power amplifier?
A. To balance the transmitter audio frequency response
B. To reduce harmonic radiation
C. To reduce distortion due to excessive drive
D. To increase overall efficiency
C. To reduce distortion due to excessive drive
What type of device is often used to enable matching the transmitter output to an impedance other than 50 ohms?
A. Balanced modulator
B. SWR Bridge
C. Antenna coupler
D. Q Multiplier
C. Antenna coupler
What condition can lead to permanent damage when using a solid-state RF power amplifier?
A. Exceeding the Maximum Usable Frequency
B. Low input SWR
C. Shorting the input signal to ground
D. Excessive drive power
D. Excessive drive power
What is the correct adjustment for the load or coupling control of a vacuum tube RF power amplifier?
A. Minimum SWR on the antenna
B. Minimum plate current without exceeding maximum allowable grid current
C. Highest plate voltage while minimizing grid current
D. Maximum power output without exceeding maximum allowable plate current
D. Maximum power output without exceeding maximum allowable plate current
Why is a time delay sometimes included in a transmitter keying circuit?
A. To prevent stations from talking over each other
B. To allow the transmitter power regulators to charge properly
C. To allow time for transmit-receive changeover operations to complete properly before RF output is allowed
D. To allow time for a warning signal to be sent to other stations
C. To allow time for transmit-receive changeover operations to complete properly before RF output is allowed
What is the purpose of an electronic keyer?
A. Automatic transmit/receive switching
B. Automatic generation of strings of dots and dashes for CW operation
C. VOX operation
D. Computer interface for PSK and RTTY operation
B. Automatic generation of strings of dots and dashes for CW operation
Which of the following is a use for the IF shift control on a receiver?
A. To avoid interference from stations very close to the receive frequency
B. To change frequency rapidly
C. To permit listening on a different frequency from that on which you are transmitting
D. To tune in stations that are slightly off frequency without changing your transmit frequency
A. To avoid interference from stations very close to the receive frequency
Which of the following is a common use for the dual VFO feature on a transceiver?
A. To allow transmitting on two frequencies at once
B. To permit full duplex operation, that is transmitting and receiving at the same time
C. To permit ease of monitoring the transmit and receive frequencies when they are not the same
D. To facilitate computer interface
C. To permit ease of monitoring the transmit and receive frequencies when they are not the same
What is one reason to use the attenuator function that is present on many HF transceivers?
A. To reduce signal overload due to strong incoming signals
B. To reduce the transmitter power when driving a linear amplifier
C. To reduce power consumption when operating from batteries
D. To slow down received CW signals for better copy
A. To reduce signal overload due to strong incoming signals
How should the transceiver audio input be adjusted when transmitting PSK31 data signals?
A. So that the transceiver is at maximum rated output power
B. So that the transceiver ALC system does not activate
C. So that the transceiver operates at no more than 25% of rated power
D. So that the transceiver ALC indicator shows half scale
B. So that the transceiver ALC system does not activate
What item of test equipment contains horizontal and vertical channel amplifiers?
A. An ohmmeter
B. A signal generator
C. An ammeter
D. An oscilloscope
D. An oscilloscope
Which of the following is an advantage of an oscilloscope versus a digital voltmeter?
A. An oscilloscope uses less power
B. Complex impedances can be easily measured
C. Input impedance is much lower
D. Complex waveforms can be measured
D. Complex waveforms can be measured
Which of the following is the best instrument to use when checking the keying waveform of a CW transmitter?
A. An oscilloscope
B. A field-strength meter
C. A sidetone monitor
D. A wavemeter
A. An oscilloscope
What signal source is connected to the vertical input of an oscilloscope when checking the RF envelope pattern of a transmitted signal?
A. The local oscillator of the transmitter
B. An external RF oscillator
C. The transmitter balanced mixer output
D. The attenuated RF output of the transmitter
D. The attenuated RF output of the transmitter
Why is high input impedance desirable for a voltmeter?
A. It improves the frequency response
B. It decreases battery consumption in the meter
C. It improves the resolution of the readings
D. It decreases the loading on circuits being measured
D. It decreases the loading on circuits being measured
What is an advantage of a digital voltmeter as compared to an analog voltmeter?
A. Better for measuring computer circuits
B. Better for RF measurements
C. Better precision for most uses
D. Faster response
C. Better precision for most uses
Which of the following might be a use for a field strength meter?
A. Close-in radio direction-finding
B. A modulation monitor for a frequency or phase modulation transmitter
C. An overmodulation indicator for a SSB transmitter
D. A keying indicator for a RTTY or packet transmitter
A. Close-in radio direction-finding
Which of the following instruments may be used to monitor relative RF output when making antenna and transmitter adjustments?
A. A field-strength meter
B. An antenna noise bridge
C. A multimeter
D. A Q meter
A. A field-strength meter
Which of the following can be determined with a field strength meter?
A. The radiation resistance of an antenna
B. The radiation pattern of an antenna
C. The presence and amount of phase distortion of a transmitter
D. The presence and amount of amplitude distortion of a transmitter
B. The radiation pattern of an antenna
Which of the following can be determined with a directional wattmeter?
A. Standing wave ratio
B. Antenna front-to-back ratio
C. RF interference
D. Radio wave propagation
A. Standing wave ratio
Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
A. Receiver
B. Transmitter
C. Antenna and feed line
D. All of these choices are correct
C. Antenna and feed line
What problem can occur when making measurements on an antenna system with an antenna analyzer?
A. SWR readings may be incorrect if the antenna is too close to the Earth
B. Strong signals from nearby transmitters can affect the accuracy of measurements
C. The analyzer can be damaged if measurements outside the ham bands are attempted
D. Connecting the analyzer to an antenna can cause it to absorb harmonics
B. Strong signals from nearby transmitters can affect the accuracy of measurements