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Frequency-exchange signaling

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionFeb 24, 2022
Entity authorityQ5502842 ↗
Source-derived summary

In telegraphy, frequency-exchange signaling or two-source frequency keying is frequency-change signaling in which the change from one significant condition to another is accompanied by decay in amplitude of one or more frequencies and by buildup in amplitude of one or more other frequencies.

Frequency-exchange signaling applies to supervisory signaling and user-information transmission.

See also

Keying (telecommunications)

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

The public source identifies “Frequency-exchange signaling” as open-knowledge reference entry. This brief keeps that definition visible, then builds a research path around Frequency-exchange, signaling and Open-knowledge.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—2022—that can be checked directly. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with Frequency-exchange, signaling and Open-knowledge providing the first useful test.
Editorial analysis

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A short description can identify a subject without explaining its stakes. For “Frequency-exchange signaling”, the useful work is to connect “open-knowledge reference entry” to the records capable of establishing context and consequence.

Evidence profile

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 Feb 24, 2022. The linked authority identifier is Q5502842. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2022.

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Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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  2. Expand the search: follow Frequency-exchange signaling primary sources, Frequency-exchange signaling archive and Frequency-exchange research across catalogues and specialist indexes.
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Source & attribution

This entry incorporates text from “Frequency-exchange 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.