SUBELEMENT G4 - AMATEUR RADIO PRACTICES Flashcards
G4A01 (B)
What is the purpose of the “notch filter” found on many HF transceivers?
B. To reduce interference from carriers in the receiver passband
G4A02 (C)
What is one advantage of selecting the opposite or “reverse” sideband when receiving CW signals on a typical HF transceiver?
C. It may be possible to reduce or eliminate interference from other signals
G4A03 (C)
What is normally meant by operating a transceiver in “split” mode?
C. The transceiver is set to different transmit and receive frequencies
G4A04 (B)
What reading on the plate current meter of a vacuum tube RF power amplifier indicates correct adjustment of the plate tuning control?
B. A pronounced dip
G4A05 (C)
What is a reason to use Automatic Level Control (ALC) with an RF power amplifier?
C. To reduce distortion due to excessive drive
G4A06 (C)
What type of device is often used to match transmitter output impedance to an impedance not equal to 50 ohms?
C. Antenna coupler or antenna tuner
G4A07 (D)
What condition can lead to permanent damage to a solid-state RF power amplifier?
D. Excessive drive power
G4A08 (D)
What is the correct adjustment for the load or coupling control of a vacuum tube RF power amplifier?
D. Maximum power output without exceeding maximum allowable plate current
G4A09 (C)
Why is a time delay sometimes included in a transmitter keying circuit?
C. To allow time for transmit-receive changeover operations to complete properly before RF output is allowed
G4A10 (B)
What is the purpose of an electronic keyer?
B. Automatic generation of strings of dots and dashes for CW operation
G4A11 (A)
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
G4A12 (C)
Which of the following is a common use for the dual VFO feature on a transceiver?
C. To permit monitoring of two different frequencies
G4A13 (A)
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
G4A14 (B)
What is likely to happen if a transceiver’s ALC system is not set properly when transmitting AFSK signals with the radio using single sideband mode?
B. Improper action of ALC distorts the signal and can cause spurious emissions
G4A15 (D)
Which of the following can be a symptom of transmitted RF being picked up by an audio cable carrying AFSK data signals between a computer and a transceiver?
A. The VOX circuit does not un-key the transmitter
B. The transmitter signal is distorted
C. Frequent connection timeouts
D. All of these choices are correct
G4B01 (D)
What item of test equipment contains horizontal and vertical channel amplifiers?
D. An oscilloscope
G4B02 (D)
Which of the following is an advantage of an oscilloscope versus a digital voltmeter?
D. Complex waveforms can be measured
G4B03 (A)
Which of the following is the best instrument to use when checking the keying waveform of a CW transmitter?
A. An oscilloscope
G4B04 (D)
What signal source is connected to the vertical input of an oscilloscope when checking the RF envelope pattern of a transmitted signal?
D. The attenuated RF output of the transmitter
G4B05 (D)
Why is high input impedance desirable for a voltmeter?
D. It decreases the loading on circuits being measured
G4B06 (C)
What is an advantage of a digital voltmeter as compared to an analog voltmeter?
C. Better precision for most uses
G4B07 (B)
What signals are used to conduct a two-tone test?
B. Two non-harmonically related audio signals
G4B08 (A)
Which of the following instruments may be used to monitor relative RF output when making antenna and transmitter adjustments?
A. A field strength meter
G4B09 (B)
Which of the following can be determined with a field strength meter?
B. The radiation pattern of an antenna
G4B10 (A)
Which of the following can be determined with a directional wattmeter?
A. Standing wave ratio
G4B11 (C)
Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
C. Antenna and feed line