• Country
• United States of America (USA)

• Manufacturer / Brand
• Keithley Instruments Inc.; Cleveland (OH)

• Year
• 1966

• Category
• Service- or Lab Equipment

• Radiomuseum.org ID
• 282623

Click on the schematic thumbnail to request the schematic as a free document.

• Number of Tubes
• 4

• Valves / Tubes
• 12AU7 7025 12AT7 12AU7 0B2 0A2

• Wave bands
• - without

• Power type and voltage
• Alternating Current supply (AC) / 50-60Hz, 105-125/210-250 Volt

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: Microvolt Ammeter 153 - Keithley Instruments Inc.;

• Shape
• Tablemodel, with any shape - general.

• Dimensions (WHD)
• 175 x 275 x 285 mm / 6.9 x 10.8 x 11.2 inch

• Notes

• Voltmeter, ammeter, null detector.  Measuring amplifier can be decoupled by removing a link from the chassis PE potential for "floating measurements".
  
  Input Connector: Triaxial
  
  Display selectable: Meter switch selects left-zero (positive or negative) or center-zero scale.  Recorder output polarity is not reversed.
  
  Voltmeter range: 10uV full scale to 1000V 5μV in 17 overlapping 1x and 3x ranges
  Input resistance: > 20 to 200MΩ (depending on range), 2 megohm shunt enabled with Function switch
  
  Accuracy in percent of full scale:
  ± 1% of full scale on 3 mV - 1000V range
  ± 2% of full scale on 100μV - 1mV range
  ± 3% of full scale on 10μV - 30μV range
  
  Current measurement after the shunt / voltage drop method
  
  Ammeter measuring range
  5pA to 100mA in 21 areas
  Accuracy 2% FS
  
  Inherent noise <0.06μV rms (Shorted input), Self Drift: ± 2μV/day
  
  Recorder output on the rear panel, 0 to ± 1V

  Voltmeter, Amperemeter, Null-Detektor
  Messverstärker kann für "schwimmende Messungen" durch Auftrennen einer Brücke vom Chassis-PE-Potential entkoppelt werden.

  
  Eingangsbuchse: Triaxial

  Anzeige wählbar:
  +, -,  Nullpunkt links
  0V-Skalenmitte

  Voltmeter Messbereich 5µV bis 1000V in 17 Bereichen
  Eingangswiderstand:
  >20 .... 200MΩ± (abhängig vom Messbereich)
  'Mit Schalter auf 2 MΩ reduzierbar

  Messgenauigkeit in Prozent vom Skalenendwert:
  ± 1% im Bereich 3mV - 1000V
  ± 2% im Bereich 100µV - 1mV
  ± 3% im Bereich 30µV - 30 µV

  Strommessung nach der Shunt/Spannungsabfall-Methode

  Amperemeter Messbereich
  5pA bis 100mA in 21 Bereichen
  Messgenauigkeit 2% vom Skalenendwert
  
  Eigenrauschen <0,06µV rms (bei kurzgeschlossenem Eingang)
  Eigendrift: 2µV / Tag

  Recorder Ausgang auf der Geräterückseite, Pegel 0 bis ±1V

• Net weight (2.2 lb = 1 kg)
• 5.9 kg / 12 lb 15.9 oz (12.996 lb)

• Price in first year of sale
• 550.00 $

• Source of data
• - - Manufacturers Literature

• Author
• Model page created by Fred Mandel. See "Data change" for further contributors.

• Other Models

• Here you find 38 models, 33 with images and 16 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Keithley Instruments Inc.; Cleveland (OH)