Logging in (or registering) will help the system to select questions that you need to focus on.
Which of the following properties is important in estimating whether an RF signal exceeds the maximum permissible exposure (MPE)?
What is the purpose of a power supply interlock?
Which of the following frequencies is within the General class portion of the 80-meter band?
Which of the following transmissions is permitted?
What is the maximum transmitting power an amateur station may use on the 12-meter band?
Which of the following criteria must be met for a non-U.S. citizen to be an accredited Volunteer Examiner?
Which of the following conditions require a licensed Amateur Radio operator to take specific steps to avoid harmful interference to other users or facilities?
Which of the following is an advantage when using single sideband, as compared to other analog voice modes on the HF amateur bands?
What is the first thing you should do if you are communicating with another amateur station and hear a station in distress break in?
What does the Q signal "QSL" mean?
What is QRP operation?
What segment of the 80-meter band is most commonly used for digital transmissions?
How long does it take charged particles from coronal mass ejections to affect radio propagation on Earth?
What is the approximate maximum distance along the Earth's surface that is normally covered in one hop using the F2 region?
What does the term "critical angle" mean, as used in radio wave propagation?
Which of the following is a common use for the dual-VFO feature on a transceiver?
Which of the following can be determined with a field strength meter?
Which of the following could be a cause of interference covering a wide range of frequencies?
What frequency range is occupied by a 3 kHz LSB signal when the displayed carrier frequency is set to 7.178 MHz?
What is the name of the process by which sunlight is changed directly into electricity?
What is one reason to use an impedance matching transformer?
How many watts are dissipated when a current of 7.0 milliamperes flows through a 1250 ohm resistance?
If three equal value resistors in series produce 450 ohms, what is the value of each resistor?
What is an advantage of the low internal resistance of nickel-cadmium batteries?
How does a ferrite bead or core reduce common-mode RF current on the shield of a coaxial cable?
Which of the following components are used in a power supply filter network?
What is the reason for neutralizing the final amplifier stage of a transmitter?
What is the phase difference between the I and Q signals that software-defined radio (SDR) equipment uses for modulation and demodulation?
Which of the following is an effect of overmodulation?
What process combines two signals in a non-linear circuit or connection to produce unwanted spurious outputs?
How does the receiving station respond to an ARQ data mode packet containing errors?
What might cause reflected power at the point where a feed line connects to an antenna?
Where should the radial wires of a ground-mounted vertical antenna system be placed?
How do the lengths of a three-element Yagi reflector and director compare to that of the driven element?
What is the feed-point impedance of an end-fed half-wave antenna?