General G4B: Test equipment
These are the 13 official questions in group G4B of the 2023–2027 General question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- G4B01Question 1
What item of test equipment contains horizontal and vertical channel amplifiers?
- AAn ohmmeter
- BA signal generator
- CAn ammeter
- DAn oscilloscope Correct
Why: An oscilloscope has horizontal and vertical channel amplifiers.
- G4B02Question 2
Which of the following is an advantage of an oscilloscope versus a digital voltmeter?
- AAn oscilloscope uses less power
- BComplex impedances can be easily measured
- CGreater precision
- DComplex waveforms can be measured Correct
Why: An oscilloscope can show and measure complex waveforms.
- G4B03Question 3
Which of the following is the best instrument to use for checking the keying waveform of a CW transmitter?
- AAn oscilloscope Correct
- BA field strength meter
- CA sidetone monitor
- DA wavemeter
Why: An oscilloscope is best for viewing a CW keying waveform.
- G4B04Question 4
What signal source is connected to the vertical input of an oscilloscope when checking the RF envelope pattern of a transmitted signal?
- AThe local oscillator of the transmitter
- BAn external RF oscillator
- CThe transmitter balanced mixer output
- DThe attenuated RF output of the transmitter Correct
Why: Feed the transmitter's attenuated RF output to the vertical input.
- G4B05Question 5
Why do voltmeters have high input impedance?
- AIt improves the frequency response
- BIt allows for higher voltages to be safely measured
- CIt improves the resolution of the readings
- DIt decreases the loading on circuits being measured Correct
Why: High input impedance means the meter barely loads the circuit.
- G4B06Question 6
What is an advantage of a digital multimeter as compared to an analog multimeter?
- ABetter for measuring computer circuits
- BLess prone to overload
- CHigher precision Correct
- DFaster response
Why: Digital multimeters offer higher precision.
- G4B07Question 7
What signals are used to conduct a two-tone test?
- ATwo audio signals of the same frequency shifted 90 degrees
- BTwo non-harmonically related audio signals Correct
- CTwo swept frequency tones
- DTwo audio frequency range square wave signals of equal amplitude
Why: A two-tone test uses two non-harmonically related audio signals.
- G4B08Question 8
What transmitter performance parameter does a two-tone test analyze?
- ALinearity Correct
- BPercentage of suppression of the carrier and undesired sideband for SSB
- CPercentage of frequency modulation
- DPercentage of carrier phase shift
Why: A two-tone test checks transmitter linearity.
- G4B09Question 9
When is an analog multimeter preferred to a digital multimeter?
- AWhen testing logic circuits
- BWhen high precision is desired
- CWhen measuring the frequency of an oscillator
- DWhen adjusting circuits for maximum or minimum values Correct
Why: An analog meter's needle makes it easier to adjust for a maximum or minimum.
- G4B10Question 10
Which of the following can be determined with a directional wattmeter?
- AStanding wave ratio Correct
- BAntenna front-to-back ratio
- CRF interference
- DRadio wave propagation
Why: A directional wattmeter measures forward and reflected power, which gives SWR.
- G4B11Question 11
Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
- AReceiver
- BTransmitter
- CAntenna and feed line Correct
- DAll these choices are correct
Why: For SWR, the analyzer connects to the antenna and feed line.
- G4B12Question 12
What effect can strong signals from nearby transmitters have on an antenna analyzer?
- ADesensitization which can cause intermodulation products which interfere with impedance readings
- BReceived power that interferes with SWR readings Correct
- CGeneration of harmonics which interfere with frequency readings
- DAll these choices are correct
Why: Strong nearby signals can be picked up by the analyzer and spoil its SWR readings.
- G4B13Question 13
Which of the following can be measured with an antenna analyzer?
- AFront-to-back ratio of an antenna
- BPower output from a transmitter
- CImpedance of coaxial cable Correct
- DGain of a directional antenna
Why: An antenna analyzer can measure coax impedance.