GB938099A - Improvements in or relating to the measurement of air humidity - Google Patents

Improvements in or relating to the measurement of air humidity

Info

Publication number
GB938099A
GB938099A GB121659A GB121659A GB938099A GB 938099 A GB938099 A GB 938099A GB 121659 A GB121659 A GB 121659A GB 121659 A GB121659 A GB 121659A GB 938099 A GB938099 A GB 938099A
Authority
GB
United Kingdom
Prior art keywords
capacitance
jan
sense
current
energized
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB121659A
Inventor
Dermot Aelfred Richards
Thomas Symington Mcleod
Christopher Mark Deavin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Plessey Co Ltd
Original Assignee
Plessey Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to NL247250D priority Critical patent/NL247250A/xx
Application filed by Plessey Co Ltd filed Critical Plessey Co Ltd
Priority to GB121659A priority patent/GB938099A/en
Priority to BE586529A priority patent/BE586529A/en
Priority to FR815519A priority patent/FR1245222A/en
Publication of GB938099A publication Critical patent/GB938099A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/22—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
    • G01N27/223—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity
    • G01N27/225—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity by using hygroscopic materials

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

938,099. Measuring bridges. PLESSEY CO. Ltd. Jan. 13, 1960 [Jan. 13, 1959; Jan. 15, 1959], Nos. 1216/59 and 1475/59. Class 37. [Also in Groups XXXVIII and XL (c)] Apparatus for measuring capacitance comprises a tuned transistor R.F. oscillator A energized from a D.C. source G to excite a diagonal of a bridge containing a test capacitance 15, a reference capacitance 14, and windings 10, 11 on a toroidal core also having a winding 12 developing an unbalance voltage whose phase sense, referred to the current in winding 11, and amplitude denote the sense and magnitude of the deviation in value of capacitance 15 referred to capacitance 14. This voltage is transistor amplified at C and transformer coupled to a phase-sensitive detector D also energized from oscillator A to produce in instrument F a current indicating in sense and amplitude the deviation of capacitance 15 irrespective of resistive current therein.
GB121659A 1959-01-13 1959-01-13 Improvements in or relating to the measurement of air humidity Expired GB938099A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
NL247250D NL247250A (en) 1959-01-13
GB121659A GB938099A (en) 1959-01-13 1959-01-13 Improvements in or relating to the measurement of air humidity
BE586529A BE586529A (en) 1959-01-13 1960-01-13 Improvements relating to the measurement of the moisture content of a strip of material, in particular of fibrous material
FR815519A FR1245222A (en) 1959-01-13 1960-01-13 Apparatus for measuring the moisture content of a sheet of material, in particular a sheet of paper

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB121659A GB938099A (en) 1959-01-13 1959-01-13 Improvements in or relating to the measurement of air humidity

Publications (1)

Publication Number Publication Date
GB938099A true GB938099A (en) 1963-09-25

Family

ID=9718150

Family Applications (1)

Application Number Title Priority Date Filing Date
GB121659A Expired GB938099A (en) 1959-01-13 1959-01-13 Improvements in or relating to the measurement of air humidity

Country Status (1)

Country Link
GB (1) GB938099A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3302459A (en) * 1963-10-18 1967-02-07 Hitachi Ltd Device for admittance measurements by converting admittance into direct current
US3355664A (en) * 1964-06-12 1967-11-28 Rome Cable Corp Apparatus for measuring insulation thickness of coated conductors
GB2203558A (en) * 1987-04-10 1988-10-19 Seismograph Service Seismic geophone impedance measurement

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3302459A (en) * 1963-10-18 1967-02-07 Hitachi Ltd Device for admittance measurements by converting admittance into direct current
US3355664A (en) * 1964-06-12 1967-11-28 Rome Cable Corp Apparatus for measuring insulation thickness of coated conductors
GB2203558A (en) * 1987-04-10 1988-10-19 Seismograph Service Seismic geophone impedance measurement
GB2203558B (en) * 1987-04-10 1991-08-14 Seismograph Service Seismic geophone test apparatus

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