General Class

Which type of code is used for sending characters in a PSK31 signal?

What is indicated on a waterfall display by one or more vertical lines on either side of a data mode or RTTY signal?

Which of the following describes a waterfall display?

What does an FT8 signal report of +3 mean?

Which of the following provide digital voice modes?

Which of the following factors determine the characteristic impedance of a parallel conductor feed line?

What is the relationship between high standing wave ratio (SWR) and transmission line loss?

What is the nominal characteristic impedance of “window line” transmission line?

What causes reflected power at an antenna’s feed point?

How does the attenuation of coaxial cable change with increasing frequency?

In what units is RF feed line loss usually expressed?

What must be done to prevent standing waves on a feed line connected to an antenna?

If the SWR on an antenna feed line is 5:1, and a matching network at the transmitter end of the feed line is adjusted to present a 1:1 SWR to the transmitter, what is the resulting SWR on the feed line?

What standing wave ratio results from connecting a 50-ohm feed line to a 200-ohm resistive load?

What standing wave ratio results from connecting a 50-ohm feed line to a 10-ohm resistive load?

What is the effect of transmission line loss on SWR measured at the input to the line?

What is a characteristic of a random-wire HF antenna connected directly to the transmitter?

Which of the following is a common way to adjust the feed point impedance of an elevated quarter-wave ground-plane vertical antenna to be approximately 50 ohms?

Which of the following best describes the radiation pattern of a quarter-wave ground-plane vertical antenna?

What is the radiation pattern of a dipole antenna in free space in a plane containing the conductor?