SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/ham-spst-switch-symbol

Which switch type simply opens or closes one single circuit?

Single-pole single-throw.

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  1. Single-pole single-throw ✔
  2. Single-pole double-throw
  3. Double-pole single-throw

Why: SPST means single-pole, single-throw: one circuit, one on or off contact. On the exam it is component 3 in Figure T-2.

Huh, didn't know that: A schematic shows an open SPST switch as one movable contact not touching the other.

The dad joke
Why is an SPST switch so easy to get along with? It's either on or off, no drama.
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References

Answer: Single-pole single-throw. SPST means single-pole, single-throw: one circuit, one on or off contact. On the exam it is component 3 in Figure T-2.

  1. NCVEC 2026-2030 Technician Question Pool, T6A09 ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf
    A. Single-pole single-throw
    Checked 2026-10-09.

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