• Country
• United States of America (USA)

• Manufacturer / Brand
• Beckman Instruments, Shasta, Shockley; Richmond (CA)

• Year
• 1960

• Category
• Miscellaneous (Other, Various) - see notes

• Radiomuseum.org ID
• 244963

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

• Number of Tubes
• 4

• Valves / Tubes
• 12AV7 12AV7 12AV7 12AV7

• Main principle
• none

• Wave bands
• - without

• Power type and voltage
• Powered by external power supply or a main unit. / AC 6.3 & DC 210 Volt

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case, TUBES VISIBLE

• from Radiomuseum.org
• Model: Decimal Counting Unit 785A - Beckman Instruments, Shasta,

• Shape
• Chassis only or for «building in»

• Dimensions (WHD)
• 34 x 150 x 120 mm / 1.3 x 5.9 x 4.7 inch

• Notes

• The Model 785A is a direct-reading, plug-in decimal counting unit. A decimal counting unit (DCU) registers voltage pulses applied at an input. Starting from zero it counts to nine, returning to zero on the tenth pulse and simultaneously generating an output signal. The count score is indicated by the illumination of one of ten neon lights placed behind a numbered acetate panel.

  Count Indication: Illuminated decimal digits
  Input Requirements: Negative pulses. (See "OPERATION")
  Resolution of Paired Pulses:  0.8 microseconds
  Maximum Counting Rate: 1,100,000 counts per second
  
  Output Characteristics: Designed to drive a Model775 DCU or any modification of it except a 775LJ.

  NOTE: The 785A will also drive the 705 series DCU's since the latter are interchangeable with the 775 series.

  Reset: Reset to zero by negative pulse applied to pin 8 of plug.
  
  Power Requirements:
    Heaters: 6.3V a-c at 1.8 amps near ground potential.
    Plates: 175 to 260 volts. (Design center is 210 volts at 45 ma.)

  Construction:
  Plug-in unit which fits into standard 11-pin tube socket.

• Net weight (2.2 lb = 1 kg)
• 0.256 kg / 0 lb 9 oz (0.564 lb)

• Source of data
• -- Original-techn. papers.

• Author
• Model page created by Pius Steiner. See "Data change" for further contributors.

• Other Models

• Here you find 51 models, 43 with images and 18 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Beckman Instruments, Shasta, Shockley; Richmond (CA)