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Frequency-change signaling

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 10, 2026
Entity authorityQ5502839 ↗
Source-derived summary

In telecommunications, frequency-change signaling is a telegraph signaling method in which one or more particular frequencies correspond to each desired signaling condition of a telegraph code. The transition from one set of frequencies to the other may be a continuous or a discontinuous change in the frequency or phase.

See also

Frequency-shift keying

Frequency modulation

References

This article incorporates public domain material from Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22. (in support of MIL-STD-188).

Editorial summary

This brief starts where responsible research should: with the source description of “Frequency-change signaling” as open-knowledge reference entry. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—2022—that can be checked directly. The selected authority fields contribute no independent date. The account is most persuasive where Frequency-change, signaling and Open-knowledge can be independently traced.
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The subject matters to the general reference register because the source frames it as open-knowledge reference entry. Its deeper value depends on whether names, dates, institutions and citations support that framing.

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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 10, 2026. The linked authority identifier is Q5502839. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2022.

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Source & attribution

This entry incorporates text from “Frequency-change signaling” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.