WorksheetsHam Radio Extra Questions Till 2020 Set E4A
Total questions: 15
Worksheet time: 15mins
Name
Class
Date
1.
E4A01 Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?
a)
A. Input capacitance
b)
B. Input impedance
c)
C. Sampling rate
d)
D. Sample resolution
2.
E4A02 Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?
a)
A. RF amplitude and time
b)
B. RF amplitude and frequency
c)
C. SWR and frequency
d)
D. SWR and time
3.
E4A03 Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?
a)
A. A wattmeter
b)
B. A spectrum analyzer
c)
C. A logic analyzer
d)
D. A time-domain reflectometer
4.
E4A04 What determines the upper frequency limit for a computer soundcard-based oscilloscope program?
a)
A. Analog-to-digital conversion speed of the soundcard
b)
B. Amount of memory on the soundcard
c)
C. Q of the interface of the interface circuit
d)
D. All of these choices are correct
5.
E4A05 What might be an advantage of a digital vs an analog oscilloscope?
a)
A. Automatic amplitude and frequency numerical readout
b)
B. Storage of traces for future reference
c)
C. Manipulation of time base after trace capture
d)
D. All of these choices are correct
6.
E4A06 What is the effect of aliasing in a digital or computer-based oscilloscope?
a)
A. False signals are displayed
b)
B. All signals will have a DC offset
c)
C. Calibration of the vertical scale is no longer valid
d)
D. False triggering occurs
7.
E4A07 Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?
a)
A. Antenna analyzers automatically tune your antenna for resonance
b)
B. Antenna analyzers do not need an external RF source
c)
C. Antenna analyzers display a time-varying representation of the modulation envelope
d)
D. All of these choices are correct
8.
E4A08 Which of the following instrument would be best for measuring the SWR of a beam antenna?
a)
A. A spectrum analyzer
b)
B. A Q meter
c)
C. An ohmmeter
d)
D. An antenna analyzer
9.
E4A09 When using a computer’s soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?
a)
A. The same as the sample rate
b)
B. One-half the sample rate
c)
C. One-tenth the sample rate
d)
D. It depends on how the data is stored internally
10.
E4A10 Which of the following displays multiple digital signal states simultaneously?
a)
A. Network analyzer
b)
B. Bit error rate tester
c)
C. Modulation monitor
d)
D. Logic analyzer
11.
E4A11 Which of the following is good practice when using an oscilloscope probe?
a)
A. Keep the signal ground connection of the probe as short as possible
b)
B. Never use a high impedance probe to measure a low impedance circuit
c)
C. Never use a DC-coupled probe to measure an AC circuit
d)
D. All of these choices are correct
12.
E4A12 Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?
a)
A. Use high quality double shielded coaxial cables to reduce signal losses
b)
B. Attenuate the transmitter output going to the spectrum analyzer
c)
C. Match the antenna to the load
d)
D. All of these choices are correct
13.
E4A13 How is the compensation of an oscilloscope probe typically adjusted?
a)
A. A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
b)
B. A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
c)
C. A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
d)
D. A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
14.
E4A14 What is the purpose of the prescaler function on a frequency counter?
a)
A. It amplifies low level signals for more accurate counting
b)
B. It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
c)
C. It prevents oscillation in a low-frequency counter circuit
d)
D. It divides a higher frequency signal so a low-frequency counter can display the input frequency
15.
E4A15 What is an advantage of a period-measuring frequency counter over a direct-count type?
a)
A. It can run on battery power for remote measurements
b)
B. It does not require an expensive high-precision time base
c)
C. It provides improved resolution of low-frequency signals within a comparable time period
d)
D. It can directly measure the modulation index of an FM transmitter
100 %
