Updated: Dec 9, 2025 | Source: 2024-2028 Question Pool | Topic: E3B
E3B09E3B

At what time of year is sporadic-E propagation most likely to occur?

Deep Dive: E3B09

The correct answer is A: Around the solstices, especially the summer solstice. At what time of year is sporadic-E propagation most likely to occur is around the solstices, especially the summer solstice. Sporadic-E is most common around solstices, with summer solstice being peak. For amateur radio operators, this is important for sporadic-E operation. Understanding this helps when operating sporadic-E.

Why Other Answers Are Wrong

Option B: Incorrect. Around solstices, especially winter solstice isn't correct - summer solstice is peak, not winter. Winter solstice isn't peak. Option C: Incorrect. Around equinoxes, especially spring equinox isn't correct - sporadic-E is around solstices, not equinoxes. Equinoxes isn't the time. Option D: Incorrect. Around equinoxes, especially fall equinox isn't correct - sporadic-E is around solstices, not equinoxes. Equinoxes isn't the time.

Exam Tip

Sporadic-E time of year = around solstices, especially summer solstice. Think 'S'poradic-'E' = 'S'ummer 'E'quator (solstice). Sporadic-E is most common around solstices, with summer solstice being peak. Not winter solstice, not equinoxes - just solstices, especially summer.

Memory Aid

Sporadic-E time of year = around solstices, especially summer solstice. Think 'S'poradic-'E' = 'S'ummer 'S'olstice. Sporadic-E is most common around solstices, with summer solstice being peak. Important for sporadic-E operation.

Real-World Example

Sporadic-E propagation: It's most likely to occur around the solstices (June and December), especially the summer solstice (June). Sporadic-E activity peaks during summer months. This is the time of year - around solstices, especially summer solstice.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E3B

Reference: 2024-2028 Question Pool · E3 - Radio Wave Propagation

Key Concepts

Sporadic-E propagation Time of year Around solstices Summer solstice

Verified Content

Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E3B topic.