SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/ham-short-heavy-power-wires

Why use short, heavy-gauge wires for a radio's DC power connection?

To minimize voltage drop when transmitting.

  1. To avoid RF interference
  2. To match the power supply impedance
  3. To minimize voltage drop when transmitting ✔

Why: A radio pulls lots of current when it transmits. Thin or long wires waste voltage, so short, thick wires keep the voltage up.

Huh, didn't know that: A typical 50-watt mobile radio needs about 13.8 volts at 12 amps.

The dad joke
Why did the thin wire quit? It could not handle the current pressure.
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Sources

  1. NCVEC 2026-2030 Technician Question Pool (Element 2), errata Feb 19, 2026 https://www.ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf

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