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Research draft

horn

vr.tr.horn · PHY.OBJ

Enable an AI agent to recognise an audible signalling horn, assess its readiness and decide whether and how it may be sounded, tested or serviced.

Thing Registry Physical world and living systems

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

recalled by Codex without web access - no source was read

Researched by: Codex

Purpose and description

Enable an AI agent to recognise an audible signalling horn, assess its readiness and decide whether and how it may be sounded, tested or serviced.

A horn is an acoustic signalling device that produces a conspicuous sound, typically through an electrically driven diaphragm or a pressurised gas supply, to warn others or attract attention.

It can be Classify a candidate signalling device and flag unresolved horn-versus-siren or horn-versus-instrument boundaries.; Check compatibility with a proposed electrical or pneumatic supply and mounting position.; Determine whether activation or testing is appropriate under the documented operating and acoustic constraints.; Compare measured sound output with a specified requirement or a previous verified baseline.; Diagnose weak, intermittent, absent or continuous unintended sounding.; Identify supported cleaning, adjustment, repair or replacement actions and the checks needed before return to service..

Distinguishing features

Its intended output is an audible signal for warning or communication, rather than musical performance; sound alone may not resolve this boundary.

The modelled assembly generates a signal when supplied with its required actuation and energy, rather than serving solely as a passive flared acoustic attachment.

Its identity depends on the sound-producing assembly and signalling role, not merely on having a horn-shaped exterior.

A rotating siren mechanism, struck bell or general-purpose audio speaker calls for a neighbouring classification unless registry evidence explicitly includes it.

The registered kind remains distinct from a manufacturer's horn product, an installed unit and an individual sounding event.

Scope

+ Audible signalling horns operated electrically, pneumatically or by direct manual effort

+ Sound-generating elements and integral resonators or flared outlets

+ Horn-specific activation, power or pressure requirements and operating states

+ Acoustic output, signal patterns and intended warning or communication function

+ Mounting, environmental exposure, inspection and serviceability

- Musical horns and their performance techniques

- Animal horns, horn tissue and objects classified primarily by that material

- Passive acoustic horns used only to direct or couple sound from a separate source

- Complete vehicles, vessels or alarm systems that incorporate a horn

- Sirens, bells and general-purpose loudspeakers classified as neighbouring signalling devices

Characteristics

Signalling application
vehicle warning; marine signalling; industrial warning; handheld signalling; other; unresolved Determines which signal meanings, installation constraints and operating rules require research.
Sound-generation mechanism
electromagnetically driven diaphragm; pressure-driven diaphragm or reed; electronic transducer; other; unknown Identifies the relevant supply requirements, faults and service actions.
Energy and supply requirements
As applicable: V, A, W, pressure in kPa with gauge or absolute basis, airflow in L/min with reference conditions Supports compatibility checks and distinguishes inadequate supply from a failed horn.
Acoustic output
Sound pressure level in dB with weighting, distance, direction, operating conditions and test method recorded An unqualified loudness number cannot establish signal effectiveness or exposure.
Frequency content
Hz for measured fundamental, dominant frequencies or frequency range, with method stated Helps assess signal recognition, masking and changes associated with faults.
Actuation and signal behaviour
momentary; latched; externally timed; internally patterned; single-tone; multi-tone; other Determines what an activation command produces and how sounding stops.
Operating duration limits
Maximum sounding duration in s and duty cycle in %, where specified Constrains testing and repeated operation against overheating or supply depletion.
Installation interfaces
Mount, electrical supply or air supply, actuator or controller, host equipment Locates the dependencies that must be checked before installation or fault diagnosis.
Readiness
unverified; ready; degraded; inoperative; isolated; sounding unintentionally Separates an observed operating state from an unsupported assumption of readiness.
Applicable requirements and evidence
Identified issuing body, document edition, application, jurisdiction and supporting test or approval record Allows a compliance claim to be evaluated for the actual horn and installation.

Also called

electromagnetically operated hornGerman hornOrlocor solo

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.horn-artifact

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 5 bundles · 9 layers · 16 findings · 24 questions.

Signalling identity Establishes which horn sense is intended and what its audible signal is meant to accomplish.

The registry name is ambiguous, and a signalling horn must be distinguished from both musical horns and adjacent warning devices.

Horn sense and boundary

Resolves the intended sense and the extent of the sound-producing assembly.

Signalling horn membership

Record evidence for classifying the thing as an audible signalling horn; the present sense selection remains provisional.

  1. What registry provenance establishes that horn means an audible signalling device here? provenance
  2. Does the entry own the complete sound-producing assembly or only a passive horn-shaped acoustic component? boundary

Signal purpose

Connects the horn's use to its intended listeners and signal meaning.

Intended audible message

Record whether meaning comes from simple presence of sound, tone selection or a timed sequence, and identify who controls that sequence.

  1. What warning or communication is the horn intended to convey, and to whom? definition
  2. Is the signal pattern generated within the horn, by its operator or by an external controller? boundary
Sound production and actuation Describes how energy becomes an audible signal and how sounding starts and stops.

Different horn mechanisms require different supplies, diagnostic reasoning and limits on operation.

Excitation and resonance

Identifies the sound generator, resonating components and their required supply.

Sound-generating path

Record the mechanism that initiates vibration and the components that shape or radiate the resulting sound.

  1. Which diaphragm, reed, transducer or other mechanism generates the sound, and which components shape it? definition
  2. What voltage and current, pressure and airflow, or manual input does this horn require under specified conditions? measurement

Activation and duty

Captures actuation behaviour, release behaviour and limits on repeated sounding.

Controlled sounding cycle

Record how the horn is commanded, what terminates sounding and any documented duration or recovery limits.

  1. What action starts sounding, what stops it, and what happens if the command or supply is interrupted? action
  2. What maximum sounding duration, duty cycle or recovery interval is specified, and under which supply conditions? measurement
Acoustic performance and installation Connects measurable sound output to the horn's placement and intended operating environment.

Horn effectiveness cannot be judged from nominal loudness without accounting for measurement conditions, mounting and competing sound.

Measured signal

Records reproducible evidence of loudness, frequency content and temporal behaviour.

Qualified acoustic output

Describe acoustic performance with enough test context to compare it meaningfully against a requirement or baseline.

  1. What sound pressure level is measured at a stated distance and direction, with which weighting and supply conditions? measurement
  2. What frequencies and sounding pattern characterise the signal, and what evidence shows it can be recognised in the intended background noise? measurement

Mounting and sound path

Addresses outlet orientation, obstructions, mechanical support and exposure at the installation.

Installed acoustic path

Record how the installation affects sound radiation and whether environmental exposure threatens the outlet or sound generator.

  1. What mounting envelope, outlet orientation and clearances are specified, and is the sound path obstructed? measurement
  2. What installation measures are required for water, debris, vibration or corrosion at this location? action
Readiness and permitted use Supports diagnosis, service decisions and use within documented operational requirements.

A horn may be physically present yet unable to signal effectively, or may sound when it should not; readiness and permission to operate require distinct evidence.

Faults and service

Links audible symptoms and supply observations to supported corrective actions.

Horn readiness evidence

Record the most recent functional evidence, observed symptoms and manufacturer-supported service options without assuming every horn is adjustable or repairable.

  1. Does testing show normal, weak, intermittent, absent or unintended continuous sounding, and what supply measurements accompany that observation? measurement
  2. Which isolation, cleaning, adjustment, repair or replacement steps are supported, and what test restores confidence in readiness? action

Requirements and safe testing

Associates use and testing with applicable rules, verified approvals and acoustic exposure controls.

Application-specific operation

Record requirements for the particular application and distinguish approval of a horn product from conformity of its installed configuration.

  1. Which issuing bodies, requirement editions and approval records apply to this horn's application and installed configuration? provenance
  2. Under what operating conditions may this horn be sounded or tested, and what controls address acoustic exposure and unintended signalling? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.

A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.

Reported evidence

Findings from the breadth pass, kept separate from the structural claims.

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

  • The registry records no sense; the warning-device interpretation follows the device context, but PHY.OBJ alone does not settle the ambiguity.
  • The applicable edition and scope of UN Regulation No. 28 should be checked before using it for compliance.
  • Sound pressure level, frequency and pneumatic supply pressure depend on application and design; no universal typical range is asserted.
  1. Which of these check these first hold for the sense of horn this model covers, and on what evidence? provenance

Kinds and varieties

Recalled without web access and unsourced; every item is a lead to verify.

  • Electromagnetic diaphragm horn
  • Compressed-air horn
  • Steam horn
  • Hand-squeezed bulb horn
  1. Which of these kinds and varieties hold for the sense of horn this model covers, and on what evidence? provenance

Standards and regulation

Recalled without web access and unsourced; every item is a lead to verify.

  • UN Regulation No. 28, issued within the UNECE vehicle-regulation framework, addresses audible warning devices and motor vehicles with regard to their audible signals.
  1. Which of these standards and regulation hold for the sense of horn this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

  • Warning other road users of a vehicle's presence or an immediate danger
  • Giving railway approach and operational warning signals
  • Providing audible signals aboard vessels
  • Signalling hazards around industrial equipment
  1. Which of these real-world use hold for the sense of horn this model covers, and on what evidence? provenance

Typical measurements

Recalled without web access and unsourced; every item is a lead to verify.

  • Nominal electrical supply voltage for road-vehicle horns - Commonly 12 or 24 - V DC
  1. Which of these typical measurements hold for the sense of horn this model covers, and on what evidence? provenance

Failure modes and hazards

Recalled without web access and unsourced; every item is a lead to verify.

  • Loss of electrical power, faulty wiring or a failed switch prevents sounding.
  • Diaphragm damage, corrosion or contamination weakens or distorts the sound.
  • Leaks or inadequate pressure disable or weaken pneumatic horns.
  • A stuck relay or control can cause continuous unintended sounding.
  • High sound levels can damage hearing at close range; background noise can mask the warning.
  1. Which of these failure modes and hazards hold for the sense of horn this model covers, and on what evidence? provenance

Regional variation

Recalled without web access and unsourced; every item is a lead to verify.

  • Vehicle approval requirements and restrictions on horn use vary by jurisdiction.
  • Railway and maritime signal conventions depend on the applicable operating rules.
  1. Which of these regional variation hold for the sense of horn this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Recalled without web access and unsourced; every item is a lead to verify.

  • Musical horn - A musical horn is designed for controlled musical performance; this entry describes a warning or signalling device.
  • Animal horn - An animal horn is an anatomical structure; this entry describes a manufactured acoustic device.
  • Siren - A siren typically produces a cyclically varying or pulsed warning tone; a horn typically produces a substantially steady tone while activated.
  • Acoustic horn - An acoustic horn is a flared structure that couples and directs sound; it can be a component of a signalling horn without itself generating sound.
  1. Which of these neighbouring kinds and how to tell them apart hold for the sense of horn this model covers, and on what evidence? provenance

What the second pass must settle

  • Does registry provenance confirm an audible signalling horn, or does this entry instead denote a musical horn, anatomical horn or passive acoustic horn?
  • Does an existing Vercy world model already cover this concept and therefore need to remain its single source of truth?
  • Which device families belong within the confirmed registry boundary, particularly electronic sounders and devices marketed interchangeably as horns or sirens?
  • Which authoritative application-specific requirements define acoustic tests, signal patterns, installation constraints and approval evidence?
  • What sourced ranges for dimensions, supply requirements, acoustic output, operating duration and service procedures can be stated without treating one horn family as universal?