Magnetic Drum Data Processing System Machine 650

IBM; Armonk, N.Y.

  • Year
  • 1954–1962
  • Category
  • Signal Processing and Computing
  • Radiomuseum.org ID
  • 297336

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

 Technical Specifications

  • Number of Tubes
  • 2000
  • Number of Transistors
  • Main principle
  • Special principle (see notes)
  • Wave bands
  • - without
  • Power type and voltage
  • Powered by external power supply or a main unit.
  • Loudspeaker
  • - - No sound reproduction output.
  • Material
  • Metal case
  • from Radiomuseum.org
  • Model: Magnetic Drum Data Processing System Machine 650 - IBM; Armonk, N.Y.
  • Shape
  • Boatanchor (heavy military or commercial set >20 kg).
  • Dimensions (WHD)
  • 62.125 x 30.25 x 50.75 inch / 1578 x 768 x 1289 mm
  • Notes
  • The IBM 650 Magnetic Drum Data-Processing Machine is one of IBM's early computers, and the world’s first mass-produced computer. Almost 2,000 systems were produced, the last in 1962

    The IBM 650 needs a IBM 655 Power Unit. It houses 650 power supply, translating circuitry

    Some 650 milestones - variants:
    July 14, 1953:  IBM 650 Magnetic Drum Data Processing System Machine is announced.
    December 8, 1954: The first 650 delivered to a customer.
    1955: Magnetic tape input-output and the IBM 407 accounting machine are announced as additional equipment for the 650 system.
    September 14, 1956: 650 RAMAC (which combines the IBM 650 Magnetic Drum Data Processing Machine and a series of IBM 355 disk memory units) and the 305 RAMAC are announced.
    March 30, 1959: IBM 355 Model 2 Disk Storage Unit with double capacity disk storage files for the IBM 650 is announced.
    June 12, 1959: IBM 650 Model 4 console unit is introduced.
    June 18, 1959: Double capacity magnetic drum storage for the 650 Data Processing System is announced.
    1962: The final IBM 650 is manufactured.
    August 18, 1969: The IBM 650 and its components are withdrawn from marketing (support end!).

    General information
    about 2000 tubes and 5000 Germanium diodes
    clock frequency: 125 kHz
    Storage capacity of magnetic drum:
    10,000 or 20,000 digits (1,000 or 2,000 words)
    Input units:
    IBM 533 Read-Punch Unit
    IBM 407 Accounting Machine
    IBM 727 Magnetic Tape Unit
    Output units
    IBM 533 Read-Punch Unit
    IBM 407 Accounting Machine (with Summary Punch)
    IBM 727 Magnetic Tape Unit
    Input-Output storage areas
    Independent storage areas are provided for simultaneous input and output operations.

    Approximate calculating speeds (optimally programmed)
    78,000 additions or subtractions per minute
    5,000 multiplications per minute (multiplier = 5,555,555,555)
    3,700 divisions per minute (divisor = 5,555,555,555)
    138,000 logical decisions per minute

    Floating-Point arithmetic

    Approximate calculating speeds (optimally programmed)
    35,300 floating additions or subtractions per minute (4 shifts)
    6,000 floating multiplications per minute (multiplier = 55,555,555)
    3,800 floating divisions per minute (divisor = 55,555,555)

    When a program error occurred, the computer could automatically jump back in the program and run through the program again, which meant a considerable time saving compared to manual re-entry for checking.

    It also had a magnetic drum memory, hence the official name IBM 650 Magnetic Drum Data Processing Machine.

  • Net weight (2.2 lb = 1 kg)
  • 905 kg / 1993 lb 6.3 oz (1993.392 lb)
  • Mentioned in
  • IBM History
  • Author
  • Model page created by Heribert Jung. See "Data change" for further contributors.

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