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How Volunteers Rebuilt WW2 Computers 51

nk497 writes "A single photograph, scraps of circuit diagrams drawn from memory and a pile of disused components – it isn't much to go on, but from such meager beginnings, engineers rebuilt one of the precursors to the modern computer. The Tunny decryption machine – on display at The Museum of National Computing at Bletchley Park, Buckinghamshire in the UK – was a feat of engineering both during World War II when it was created, and over the past five years when it was rebuilt by retired BT engineers."
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How Volunteers Rebuilt WW2 Computers

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  • That could be complete B.S. of course, but it looks better to me.

  • Sebastian Anthony at Extremtech has written a very nice, seven page article named "6 computer labs that gave birth to the digital world []". Bletchley Park is included, as expected.

  • What both the original engineers and the restorers accomplished given what hey had to work with.
  • OK, so I haven't RTFA... I read someplace this computer (was it called Colossus?) was first digital computer (processer, I/O, memory, etc) and not the USA's ENIAC. And that this was so ultra secret, Churchill ordered it destroyed and team members disbanded with orders to never talk about it. Thus ended the Britain's number one position in computer science and engineering. What if, this did not happen? IBM would never been regarded as the number one computer power, and we would have brought in computer peopl
    • The Tunny wasn't really a computer. It was hard coded logic for one single problem, solving the Lorentz crypto. You could not change it's function without re-engineering the hardware. All it did was to try all possible keys on a given message, and report anything that looked like a possible key. It was more a simple front end to a series of Lorentz machines, which it cranked until something interesting happened. As interesting as it was, it wasn't really what you could classify as a computer.

      The Eniac was a

    • The 'first computer' debate is complicated; there were several machines that can lay claim, depending on your definition of 'computer'. IIRC Colossus wasn't Turing-complete, see this comparison of 1940s computers. []

      The US was well on its way developing ENIAC by 1945, I don't see Colossus being published in 1945 making much of a difference.
      The first commercially available was British (Ferranti Mk 1), IBM built its lead later on.

  • by JonySuede ( 1908576 ) on Friday August 19, 2011 @03:15PM (#37146758) Journal

    The nerd won the second world war and they surly win the third.
    But will there be enough nerds left for our side to win ? If we continue to dumb down the curriculum in all levels of education, probably not.

    • But if we run after them, grab them around the waist, squeeze hard, and say "I feel your pain", they should all die of embarrassment.

      Maybe if we run them through a TSA screening, that would do them in, too.

    • The nerd won the second world war

      The nerds also lost the war, there were nerds on both sides. Nerds were responsible for mass genocide, nerds were responsible for unmanned drones and ballistic missiles landing in civilian neighborhoods, nerds/hackers created manned missiles and manned torpedoes, etc.

      But will there be enough nerds left for our side to win

      The losing side may have had the smarter nerds. The bad nerds invented the unmanned drone, ballistic missile, jet aircraft, assault rifle, night vision scope, etc. The good nerds had the advantage of laboratories that were not under attack and

  • The article indicates one of the under-appreciated values of printed circuit boards (and, later, integrated circuits): The ability, at one process step (lithography), to connect all circuit components in a system.

    Whetter spent 18 months working alongside a volunteer on the wiring alone. “The wiring has to go between the sections, between where the rotor switches are, down to the patch panel and then to the relay control links at the bottom,” he explained. “You don’t just wire from A to B thousands of times. You have to plan it carefully and form what’s known as wiring looms.”

    To do that, precise measurements are made of the path the wires take. That’s then mapped out on a large plank of wood, with the wires threaded around nails to create the right shape. “It all sounds rather crude,” Whetter admitted.

    The 200 to 400 wires that make up each loom are laced together and then lashed to the main rack, where the soldering work starts. Whetter estimates there are 5,000 solder joints on the Tunny. “It sounds monotonous, but it’s quite an adventure, because you’re never sure if it’s going to work out,” he said. “Fortunately, we didn’t make any serious mistakes.”

    Printed circuit board techniques were just being developed [] at the time the original Tunny was built, and it is interesting to speculate on just how much time could have been saved had that technology been just a few years more advanced, and available to the original designers. Of course, having c

    • But these were basicaly all prototypes. Wires are easier to change than PCB's.

      I'd imagine they saved more time using the techniques and materials they were used to.

      (Of course the whole decryption effort became industrial as time went on - They ended up with 100's of bombes, I don't know what technologies they were using to build them towards the end when they were being built in the US).

  • Great but I believe this story is nearly 3 months old [] by now. Do you guys even bother to do even the simplest of dupe checks?

  • by Bob-taro ( 996889 ) on Friday August 19, 2011 @04:47PM (#37147922)

    IIRC, "valve" is British for "vacuum tube". When the article says the timing circuits are controlled by valves, I'm pretty sure they're talking about the electronic kind.

    • by Anonymous Coward

      The full British term is "Thermionic Valve". This describes the hot cathode (heater) within the vacuum tube and the anode is gated by the grid. A valve has similar properties to Field Effect Transistors (FET) eg. is voltage controlled.

    • by AmiMoJo ( 196126 )

      That is correct. The invention of the first electronic programmable computer was kept a secret even after the way, which is why the media back in the late 1940s claimed it was an American invention. In actual fact we (UK) did it first, but because the US one was the first to go public it defined a lot of the language and conventions for computers.

  • Just looking at all the wire used in those wire harnesses gives me a headache.
    • Clearly where the designers of my old Peugeot got their ideas from.

    • Just looking at all the wire used in those wire harnesses gives me a headache.

      When I worked at Plessey's Edge Lane, Liverpool, works in 1981 there were still women up on the fourth floor making these things while we software people downstairs next door were working to put them out of a job.

  • Technology....vacuum tubes (valves), hundreds of feet of wire, mechanical connections to break a 5 rotor cypher. Now, 70 years later, you can do the same thing basically with a small computer, laptop, tablet or smart phone.
  • by hackertourist ( 2202674 ) on Saturday August 20, 2011 @04:12AM (#37151442)

    If there's one place you should visit when you're in the UK, it's Bletchley Park [].
    Seeing the Colossus and their other rebuilt equipment in action is fabulous, and even better, some of the tour guides are the same guys who rebuilt these machines. More knowledgeable than that they don't come.

  • The National Museum of Computing []

    See also one man bravely trying to restart a 1980's mainframe without letting all the magic smoke escape and many other death defying feats.

"Hey Ivan, check your six." -- Sidewinder missile jacket patch, showing a Sidewinder driving up the tail of a Russian Su-27