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G3C05
Why is long-distance communication on the 40-, 60-, 80-, and 160-meter bands more difficult during the day?
Pick an answer to check it.
Answer: C. The D region absorbs signals at these frequencies during daylight hours
During daylight the D region forms and absorbs signals at lower frequencies like 40, 60, 80, and 160 meters. It disappears at night, which is why these bands open up for distance after dark.
Tip: Daytime D region absorbs low bands.