SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-twenty-over-s9

A signal reads 20 dB over S9. How does its power compare with an S9 signal?

100 times more powerful.

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  1. 100 times more powerful ✔
  2. 20 times more powerful
  3. 10 times less powerful

Why: Every 10 dB is a factor of 10 in power. So 20 dB is 10 times 10, which is 100 times the power.

Huh, didn't know that: An S meter measures received signal strength.

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References

Answer: 100 times more powerful. Every 10 dB is a factor of 10 in power. So 20 dB is 10 times 10, which is 100 times the power.

  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
    It is 100 times more powerful
    Checked 2026-10-10.
  2. 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
    Received signal strength
    Checked 2026-10-10.

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