Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer? A. Provide the crystal with a specified parallel inductance…

At what time of year is Sporadic E propagation most likely to occur? A. Around the solstices, especially the summer solstice B. Around the solstices, especially the winter solstice C….

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits A. It increases security B. It has more possible states than simple binary…

What is meant by circularly polarized electromagnetic waves? A. Waves with an electric field bent into a circular shape B. Waves with a rotating electric field C. Waves that circle…

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency? A. RTTY B. PACTOR C. MT63 D. PSK31 Now, I guess this answers my question about last…

What is one advantage of using ASCII code for data communications? A. It includes built in error correction features B. It contains fewer information bits per character than any other…

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference? [E1B03, 97.13] A. 1 mile B. 3 miles C. 10 miles D. 30 miles The…

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled? [E0A09] A….

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits? [E0A03] A. Use a…

What is the advantage of including a parity bit with an ASCII character stream? [E8C12] A. Faster transmission rate B. The signal can overpower interfering signals C. Foreign language characters…