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Marine Corps · SSN history

309 Telephone Operator

Appendix B lists SSN 309 as Telephone Operator in the September 1942 and June 1944 references, and as Telephone Switchboard Operator in June 1945. Its instruction, "See also 641," is a cross-reference, not an established conversion to 641 or proof that 309 was canceled.

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Documented history

Telephone Operator

June 1945 is the manual’s publication date. No effective date for a classification change is given for SSN 309.

  • Any suggested reassignment required review of the individual’s qualifications against the job specifications, rather than automatic conversion.
  • The June 1945 title does not establish equivalence with a modern occupation using the same code.
Source extraction notes

Predecessor title from the June 1944 tentative-manual column: Telephone Operator. Suggested conversions/remarks, as printed: See also 641. The Present Title column is the manual's June 1945 meaning: Telephone Switchboard Operator. It is not a present-day MOS equivalence. This is a cross-reference or instruction to review the job specification, not an explicit fixed replacement or proof of cancellation. The table gives no row-level calendar effective date. June 1945 is the manual publication date, not an inferred individual conversion date.

Source documents (1)

Reviewed September 24, 2026 against references 3 and 4.

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.