Difference between revisions of "Ham Radio Exam Questions- General"
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Q: Which of the following is an advantage of an NVIS antenna? | Q: Which of the following is an advantage of an NVIS antenna? | ||
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Revision as of 17:21, 10 November 2015
Contents
Practice Questions
Q: How are the two separate frequencies of a Frequency Shift Keyed (FSK) signal identified?
- A: Mark and Space
Q: Which of the following is an advantage of an NVIS antenna?
- A: High vertical angle radiation for working stations within a radius of a few hundred kilometers
background
FSK
FSK is commonly used for caller ID and remote metering applications. FSK is also known as frequency modulation (FM). You will often hear the terms FSK and AFSK when talking about RTTY on the HF bands. FSK means Frequency Shift Keying and AFSK means Audio Frequency Shift Keying. MARK is always the higher RF frequency and SPACE is always the lower RF frequency.
NVIS
An NVIS antenna (Near vertical incidence skywave) is a horizontally polarized radiating element that is from 1/20th wavelength (λ) to 1/4 wavelength above the ground.
