SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-alc-purpose

Why is automatic level control (ALC) used with an RF power amplifier?

To prevent excessive drive.

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  1. To reduce harmonic radiation
  2. To prevent excessive drive ✔
  3. To increase overall efficiency

Why: ALC limits how hard the transceiver drives the amplifier. Too much drive can distort the signal and splatter onto neighbors.

Huh, didn't know that: For AFSK data signals the ALC system should be inactive, because ALC action distorts the signal.

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References

Answer: To prevent excessive drive. ALC limits how hard the transceiver drives the amplifier. Too much drive can distort the signal and splatter onto neighbors.

  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
    To prevent excessive drive
    Checked 2026-10-10.

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