{
  "url": "https://openlegislation.uk/wireless-telegraphy-control-of-interference-from-radio-frequency-heating-apparatus-regulations-1971/schedule-2/part-1",
  "json_url": "https://openlegislation.uk/wireless-telegraphy-control-of-interference-from-radio-frequency-heating-apparatus-regulations-1971/schedule-2/part-1.json",
  "legislation": "uksi/1971/1675",
  "legislation_title": "The Wireless Telegraphy (Control of Interference from Radio-Frequency Heating Apparatus) Regulations 1971",
  "legislation_url": "https://openlegislation.uk/wireless-telegraphy-control-of-interference-from-radio-frequency-heating-apparatus-regulations-1971",
  "path": "schedule/2/part/1",
  "kind": "part",
  "number": "1",
  "heading": "Definition of expressions used in the Schedule",
  "text": "Voltage and e.m.f.\nReferences to the voltage or e.m.f. of a sinewave are references to its effective or root mean square value.\nDecibel (abbreviated dB)\nA unit of transmission giving the ratio of two powers.\nIf P1 and P2 represent two values of power, and n the number of decibels representing their ratio:\nn = 10 ⁢ log10 ( P1 P2 )\nIf the two powers are dissipated in equal resistive impedances, their ratio in decibels may be expressed by:\nn = 20 ⁢ log10 ( V1 V2 ) V1, V2 are the voltages across the two resistive impedances.\nTerminal voltage calibration constant\nThe number of decibels that must be added to the reading of the measuring apparatus, when a measurement of terminal voltage is made as prescribed, to give the terminal voltage in decibels above 1 microvolt.\nField strength calibration constant\nThe number of decibels that must be added to the reading of the measuring apparatus, when a measurement of field-strength is made as prescribed, to give the value of field-strength in decibels above 1 microvolt per metre.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1971/1675/schedule/2/part/1",
    "retrieved_at": "2026-10-29T22:39:37.384805+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}