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OPS-20

anti-water search radar by Japan Radio

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionAug 20, 2024
Entity authorityQ11237510
Source-derived summary

OPS-20 is a two-dimensional radar manufactured by Japan Radio. It is compatible with the Global Maritime Distress and Safety System (GMDSS) and installed as an anti-water search radar on the Maritime Self-Defense Force's escort ship. Variations include OPS-20B, OPS-20C and OPS-20E.

The model numbers of the Maritime Self-Defense Force's electronic devices, including this machine, are generally based on the naming rules for military electronic devices of the U.S. military. It is for radar mounted on surface vessels, for detection / distance direction measurement / search.

Overview

In addition, the OPS-20C is adopted by the Hyūga-class helicopter destroyer and Akizuki-class destroyer has been developed as an anti-water search radar, and is composed of two antennas, a main and a sub. Also, by changing the radar wave used from pulse wave to unmodulated continuous wave (CW), the discoverability is reduced.

On board ships

Abukuma-class destroyer escort (JS Tone)

Kongo-class destroyer

Murasame-class destroyer

Takanami-class destroyer

Atago-class destroyer

Hyūga-class helicopter destroyer

Akizuki-class destroyer

Izumo-class helicopter destroyer

Ōsumi-class tank landing ship

Uraga-class mine countermeasure vessel

Hayabusa-class patrol boat

JS Kashima

JS Chihaya

Towada-class replenishment ship

Mashū-class replenishment ship

JS Nichinan

JS Tenryū

Gallery

Citations

References

Norman Friedman (2006). The Naval Institute Guide to World Naval Weapon Systems. Naval Institute Press. ISBN 9781557502629

Self-Defense Force Equipment Yearbook 2006-2007.

Editorial summary

This brief starts where responsible research should: with the source description of “OPS-20” as anti-water search radar by Japan Radio. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA dependable orientation record for establishing vocabulary, names and a first evidence trail. The current lead gives the account dated anchors—2006, 2007—that can be checked directly. The linked authority record independently contributes the date 1969. The account is most persuasive where OPS-20, anti-water and search can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as anti-water search radar by Japan Radio. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 20, 2024. The linked authority identifier is Q11237510. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2006 and 2007.

Critical limits

A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. 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.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “OPS-20”, its source revision and the description used here.
  2. Expand the search: follow OPS-20 primary sources, OPS-20 archive and OPS-20 research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “OPS-20”?
  2. What terminology or title could unlock a more precise catalogue search?
  3. Which cited source is closest to the event, object or claim?
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Source & attribution

This entry incorporates text from OPS-20” 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.