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What does "time averaging" mean in reference to RF radiation exposure?
What is the purpose of a power supply interlock?
On which HF/MF bands is a General class license holder granted all amateur frequency privileges?
Who or what determines "good engineering and good amateur practice," as applied to the operation of an amateur station in all respects not covered by the Part 97 rules?
What is the limit for transmitter power on the 28 MHz band for a General Class control operator?
Who may receive partial credit for the elements represented by an expired Amateur Radio license?
Why should an amateur operator normally avoid transmitting on 14.100, 18.110, 21.150, 24. 930 and 28.200 MHz?
Why do most amateur stations use lower sideband on the 160-meter, 75-meter, and 40-meter bands?
Which of the following complies with good amateur practice when choosing a frequency on which to initiate a call?
What does the Q signal "QRN" mean?
Which of the following is typical of the lower HF frequencies during the summer?
What symptoms may result from other signals interfering with a PACTOR or WINMOR transmission?
How long does it take charged particles from coronal mass ejections to affect radio propagation on Earth?
What factors affect the MUF?
Why are HF scatter signals in the skip zone usually weak?
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?
What signals are used to conduct a two-tone test?
Why should soldered joints not be used with the wires that connect the base of a tower to a system of ground rods?
What frequency range is occupied by a 3 kHz USB signal with the displayed carrier frequency set to 14.347 MHz?
Which of the following direct, fused power connections would be the best for a 100 watt HF mobile installation?
What is impedance?
What is the RMS voltage of a sine wave with a value of 17 volts peak?
What is the value in microfarads of a 4700 nanofarad (nF) capacitor?
What is an advantage of the low internal resistance of nickel-cadmium batteries?
How is an LED biased when emitting light?
Which of the following is an advantage of a switchmode power supply as compared to a linear power supply?
Which of the following are basic components of a sine wave oscillator?
What circuit is used to process signals from the RF amplifier and local oscillator then send the result to the IF filter in a superheterodyne receiver?
Which of the following is characteristic of QPSK31?
What is another term for the mixing of two RF signals?
What does the number 31 represent in "PSK31"?
What must be done to prevent standing waves on an antenna feed line?
Where should the radial wires of a ground-mounted vertical antenna system be placed?
What is meant by the terms dBi and dBd when referring to antenna gain?
In which direction or directions does an electrically small loop (less than 1/3 wavelength in circumference) have nulls in its radiation pattern?