SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-g5b10

What percentage of power is lost when a circuit has a 1 dB loss?

About 20.6 percent of the power is lost.

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  1. 10.9 percent
  2. 25.9 percent
  3. 20.6 percent ✔

Why: A loss of 1 dB leaves about 79.4 percent of the power. That means 20.6 percent is lost along the way.

Huh, didn't know that: Every 10 dB is a factor of ten in power, so a 10 dB loss leaves only one tenth.

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Two atoms bump into each other. One says, 'I lost an electron!' The other asks, 'Are you sure?' 'I'm positive!'
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References

Answer: 20.6 percent. A loss of 1 dB leaves about 79.4 percent of the power. That means 20.6 percent is lost along the way.

  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
    20.6 percent
    Checked 2026-10-11.

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