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Manufacturer UNIVAC
Identification,ID UNIVAC-NTDS
Date of first manufacture1958
Number produced -
Estimated price or cost-
location in museum -
donor -

Contents of this page:


    (a.k.a. UNIVAC CP-642, 
    UNIVAC 1206, and AN USQ-20) 
    Remington-Rand Univac Division
    Word Length 30 bits
    Speed: 9.6 microseconds add time.
    Primary Memory: 32,768 words core memory (3.6 microseconds access time)
    Secondary  Memory: Magnetic drum and magnetic tapes,
    Instruction Set: 62 30 bit, single address instructions.
    Architecture: Parallel, binary, fixed point arithmetic, 7 index 
    registers, 1  accumulator register, 1 free register. 
    Technology: 10,702 transistors,
    Input and Output: Punched  cards,  paper tape, CRT
    Price: $500,000.
    Size: 58.6 cubic feet, 2,320 pounds, 25 kW
    Software: CS-1 compiler
    Development History: Developed under contract for the Navy 
    Tactical Data System (NTDS) by the Saint Paul division of
    Remington Rand Univac. Seymour Cray was the primary
    logic  and  circuit designer.
    Production History: The first units were  delivered in 1958/
    Later commercially available as the UNIVAC 1206  .
    Use: Real-time tactical analysis, display and control of weapons.       

See The Univac M-460 Computer which appears functionally identical and physically similar to the NTDS computer.

The following images are from "Duane"

Special features

Historical Notes
from Jan Thompson - Jan 4, 2014
I do remember that the flip-flops were all 'discretes' on a 1.25 x 2.25 circuitI board - one flip-flop per card!
I was on the USS Forrestal from 1964 - 1967, which may have been the first sea going installation of USQ-20's (?).

Mike and I taught the NTDS system at Mare Island from 1967 until I was discharged in 1970.

from Don Bryan (540) 949-1394, Feb 2004
Hi Ed,

I was a DS Tech from 1968-1976, and can provide a little more info on your NTDS computer page.
First, the link to the M460 page is nice, but the correlation is not quite accurate. The "bathtub" machine pictured at the bottom of that page, with all the I/O connectors on the left side, appears to be the original NTDS computer, the AN/USQ-17, which was designed by Seymour Cray.
The picture on your page, of the machine with front doors open, and no control panel, is the first USQ-20, or CP-642.
This machine was followed by the CP-642A (USQ-20A) and CP-642B (USQ-20B); both of which featured the control panel at the top of the machine.

For reference, check the book "When Computers Went to Sea", about the development of the NTDS system, and you can verify my information.

Don Bryan

When Computers Went to Sea : The Digitization of the United States Navy by David L. Boslaugh (Author)
List Price: $39.95
Product Details
  • Paperback: 500 pages ; Dimensions (in inches): 1.05 x 9.18 x 7.46
  • Publisher: Wiley-IEEE Computer Society Pr; (April 4, 2003)
  • ISBN: 0471472204 | All Editions
  • Average Customer Review: [4.5 stars]

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