Amateur Extra E3B: Transequatorial, long-path, chordal hop and sporadic E
These are the 13 official questions in group E3B of the 2024–2028 Amateur Extra question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- E3B01Question 1
Where is transequatorial propagation (TEP) most likely to occur?
- ABetween points separated by 2,000 miles to 3,000 miles over a path perpendicular to the geomagnetic equator Correct
- BBetween points located 1,500 miles to 2,000 miles apart on the geomagnetic equator
- CBetween points located at each other’s antipode
- DThrough the region where the terminator crosses the geographic equator
Why: TEP links points 2,000 to 3,000 miles apart across the geomagnetic equator.
- E3B02Question 2
What is the approximate maximum range for signals using transequatorial propagation?
- A1,000 miles
- B2,500 miles
- C5,000 miles Correct
- D7,500 miles
Why: TEP reaches up to about 5,000 miles.
- E3B03Question 3
At what time of day is transequatorial propagation most likely to occur?
- AMorning
- BNoon
- CAfternoon or early evening Correct
- DLate at night
Why: TEP is most likely in the afternoon or early evening.
- E3B04Question 4
What are “extraordinary” and “ordinary” waves?
- AExtraordinary waves exhibit rare long-skip propagation, compared to ordinary waves, which travel shorter distances
- BIndependently propagating, elliptically polarized waves created in the ionosphere Correct
- CLong-path and short-path waves
- DRefracted rays and reflected waves
Why: Ordinary and extraordinary waves are independent, elliptically polarized waves made in the ionosphere.
- E3B05Question 5
Which of the following paths is most likely to support long-distance propagation on 160 meters?
- AA path entirely in sunlight
- BPaths at high latitudes
- CA direct north-south path
- DA path entirely in darkness Correct
Why: 160-meter DX favors paths entirely in darkness.
- E3B06Question 6
On which of the following amateur bands is long-path propagation most frequent?
- A160 meters and 80 meters
- B40 meters and 20 meters Correct
- C10 meters and 6 meters
- D6 meters and 2 meters
Why: Long path is most frequent on 40 and 20 meters.
- E3B07Question 7
What effect does lowering a signal’s transmitted elevation angle have on ionospheric HF skip propagation?
- AFaraday rotation becomes stronger
- BThe MUF decreases
- CThe distance covered by each hop increases Correct
- DThe critical frequency increases
Why: A lower takeoff angle makes each hop cover more distance.
- E3B08Question 8
How does the maximum range of ground-wave propagation change when the signal frequency is increased?
- AIt stays the same
- BIt increases
- CIt decreases Correct
- DIt peaks at roughly 8 MHz
Why: Ground-wave range shrinks as frequency rises.
- E3B09Question 9
At what time of year is sporadic-E propagation most likely to occur?
- AAround the solstices, especially the summer solstice Correct
- BAround the solstices, especially the winter solstice
- CAround the equinoxes, especially the spring equinox
- DAround the equinoxes, especially the fall equinox
Why: Sporadic E peaks around the solstices, especially in summer.
- E3B10Question 10
What is the effect of chordal-hop propagation?
- AThe signal experiences less loss compared to multi-hop propagation, which uses Earth as a reflector Correct
- BThe MUF for chordal-hop propagation is much lower than for normal skip propagation
- CAtmospheric noise is reduced in the direction of chordal-hop propagation
- DSignals travel faster along ionospheric chords
Why: Chordal hop skips the lossy ground reflections, so signals are stronger.
- E3B11Question 11
At what time of day is sporadic-E propagation most likely to occur?
- ABetween midnight and sunrise
- BBetween sunset and midnight
- CBetween sunset and sunrise
- DBetween sunrise and sunset Correct
Why: Sporadic E is most likely between sunrise and sunset.
- E3B12Question 12
What is chordal-hop propagation?
- APropagation away from the great circle bearing between stations
- BSuccessive ionospheric refractions without an intermediate reflection from the ground Correct
- CPropagation across the geomagnetic equator
- DSignals reflected back toward the transmitting station
Why: Chordal hop is successive ionospheric refractions with no ground reflection between them.
- E3B13Question 13
What type of polarization is supported by ground-wave propagation?
- AVertical Correct
- BHorizontal
- CCircular
- DElliptical
Why: Ground wave supports vertical polarization.