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Which of these amplifier classes has the highest efficiency?

Class C.

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  1. Class A
  2. Class C ✔
  3. Class B

Why: Class C has the highest efficiency of the classes listed, ahead of Class A, B and AB. It is appropriate for FM, but not for SSB or AM.

Huh, didn't know that: In a Class A amplifier, the amplifying device conducts 100 percent of the time.

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References

Answer: Class C. Class C has the highest efficiency of the classes listed, ahead of Class A, B and AB. It is appropriate for FM, but not for SSB or AM.

  1. NCVEC 2023-2027 General Class Pool and Syllabus (6th Errata, Feb 4 2026) ncvec.org/downloads/General%20Class%20Pool%20and%20Syllabus%202023-2027%20Public%20Release%20with%206th%20Errata%20Feb%204%202026.pdf
    Class C
    Checked 2026-10-11.

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