Initial checkin

logseq/bak/pages/G3B/2025-05-01T18_48_55.966Z.Desktop.md

@@ -0,0 +1,85 @@
+G3B – Maximum Usable Frequency; Lowest Usable Frequency; short path and long path propagation; determining propagation conditions; ionospheric refraction
+
+- [[G3B01]] (D)
+What is a characteristic of skywave signals arriving at your location by both short-path and long-path propagation?
+	- A. Periodic fading approximately every 10 seconds
+	- B. Signal strength increased by 3 dB
+	- C. The signal might be cancelled causing severe attenuation
+	- D. A slightly delayed echo might be heard
+--
+- [[G3B02]] (D)
+What factors affect the MUF?
+	- A. Path distance and location
+	- B. Time of day and season
+	- C. Solar radiation and ionospheric disturbances
+	- D. All these choices are correct
+--
+- [[G3B03]] (A)
+Which frequency will have the least attenuation for long-distance skip propagation?
+	- A. Just below the MUF
+	- B. Just above the LUF
+	- C. Just below the critical frequency
+	- D. Just above the critical frequency
+--
+- [[G3B04]] (A)
+Which of the following is a way to determine current propagation on a desired band from your station?
+	- A. Use a network of automated receiving stations on the internet to see where your transmissions are being received
+	- B. Check the A-index
+	- C. Send a series of dots and listen for echoes
+	- D. All these choices are correct
+--
+- [[G3B05]] (A)
+How does the ionosphere affect radio waves with frequencies below the MUF and above the LUF?
+	- A. They are refracted back to Earth
+	- B. They pass through the ionosphere
+	- C. They are amplified by interaction with the ionosphere
+	- D. They are refracted and trapped in the ionosphere to circle Earth
+--
+- [[G3B06]] (C)
+What usually happens to radio waves with frequencies below the LUF?
+	- A. They are refracted back to Earth
+	- B. They pass through the ionosphere
+	- C. They are attenuated before reaching the destination
+	- D. They are refracted and trapped in the ionosphere to circle Earth
+--
+- [[G3B07]] (A)
+What does LUF stand for?
+	- A. The Lowest Usable Frequency for communications between two specific points
+	- B. Lowest Usable Frequency for communications to any point outside a 100-mile radius
+	- C. The Lowest Usable Frequency during a 24-hour period
+	- D. Lowest Usable Frequency during the past 60 minutes
+--
+- [[G3B08]] (B)
+What does MUF stand for?
+	- A. The Minimum Usable Frequency for communications between two points
+	- B. The Maximum Usable Frequency for communications between two points
+	- C. The Minimum Usable Frequency during a 24-hour period
+	- D. The Maximum Usable Frequency during a 24-hour period
+--
+- [[G3B09]] (C)
+What is the approximate maximum distance along the Earth’s surface normally covered in one hop using the F2 region?
+	- A. 180 miles
+	- B. 1,200 miles
+	- C. 2,500 miles
+	- D. 12,000 miles
+--
+- [[G3B10]] (B)
+What is the approximate maximum distance along the Earth’s surface normally covered in one hop using the E region?
+	- A. 180 miles
+	- B. 1,200 miles
+	- C. 2,500 miles
+	- D. 12,000 miles
+--
+- [[G3B11]] (A)
+What happens to HF propagation when the LUF exceeds the MUF?
+	- A. Propagation via ordinary skywave communications is not possible over that path
+	- B. HF communications over the path are enhanced
+	- C. Double-hop propagation along the path is more common
+	- D. Propagation over the path on all HF frequencies is enhanced
+--
+- [[G3B12]] (D)
+Which of the following is typical of the lower HF frequencies during the summer?
+	- A. Poor propagation at any time of day
+	- B. World-wide propagation during daylight hours
+	- C. Heavy distortion on signals due to photon absorption
+	- D. High levels of atmospheric noise or static