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The World's Oldest Original Digital Computer Springs Back Into Action At TNMOC
New submitter prpplague writes "After a three-year restoration project at The National Museum of Computing, the Harwell Dekatron (aka WITCH) computer will rebooted on 20 November 2012 to become the world's oldest original working digital computer. Now in its seventh decade and in its fifth home, the computer with its flashing lights and clattering printers and readers provides an awe-inspiring display for visiting school groups and the general public keen to learn about our rich computer heritage."
I highly recommend visiting bletchley park. You won't be disappointed.
With 828 dekaton counter tubes I reckon it's not a digital computer (2 base) but a decimal computer (10 base).
There are 10 kinds of people who understand binary...
It is still a digital computer (as opposed to an analogue computer), as were other non-binary false starts like the Setun which used balanced ternary.
And yet even more people who have problems with English.
Digital, as opposed to analogue, refers to the data being in discrete chunks.
You may be correct in it being a decimal computer, as opposed to a binary computer, but it is still a digital computer.
However the Dekatron valves could be made in effective binary mode (9 anodes to 1 pin) so it could still be a binary computer.
You do know that the term "digital" comes from "finger" so the origin is closer to base 10 than 2. The modern definition is something quantified by numbers rather than continuous properties. A digital encoding of 0.5 volts as the number 0.5.
This does lead on to the adage that "end the end, everything is analogue" which makes more sense if you have ever used a high-frequency storage oscilloscope.
"digital" comes from "digit" (number), which in turn comes from the latin "digitus" (finger). It has nothing to do with binary, other than binary being digital too. Any number based computer is digital. There are analog computers which use continuous currents or voltages to calculate. Those are not digital.
And yet even more people who have problems with English. Digital, as opposed to analogue, refers to the data being in discrete chunks. You may be correct in it being a decimal computer, as opposed to a binary computer, but it is still a digital computer. However the Dekatron valves could be made in effective binary mode (9 anodes to 1 pin) so it could still be a binary computer.
It was most definitely a decimal computer.
If this computer can decide to reboot itself, it must have now reached self-awareness!
...But does it run Linux?
Imagine a Beowulf cluster of those!
Dekatron valves are an example of a solution to the problem of making storage registers before integrated circuits made them essentially free. Making reliable working memory was one of the biggest problems faced by the early computer hardware designers, and Dekatron valves (tubes) were one of the more creative solutions. Of course, the reliability of solid-state electronics made them a technological backwater, but that makes them no less interesting -- it's fun to speculate on how things would have worked out if cold-cathode valves remained the dominant storage technology.
However the Dekatron valves could be made in effective binary mode (9 anodes to 1 pin) so it could still be a binary computer.
That wasn't for binary, it was for allowing less complicated tubes if they were only going to be used as divide-by-10. Instead of drawing out all 10 cathodes, cathode 0 has it's own pin, and 1-9 are on a common pin... as you only need to measure / know when cathode 0 goes high again (signifying 10 pulses have occurred).
If they only needed binary it would be a flip flop instead (either tube, for 'high' speed, sometimes glow lamps in slower things)
but yeah, absolutely digital.
Copypasta from TFA:
Power Consumption: 1.5kW
Size 2m high x 6m wide x 1m deep
Weight: 2.5 tonnes
Number of Dekaton counter tubes: 828
Number of other valves: 131
Number of relays: 480
Number of contacts or relay switches: 7073
Number of high speed relays: 26
Number of lamps: 199
Number of switches: 18
It uses about the same power as the space heater in my living room which does dim the lights across the apartment. I'd expect a museum to have slightly better power than the century-home I live in although I may be mistaken on that point.
Ever notice that Cobra Commander sounds an awful lot like Star scream?
That's like saying "this car does not run on petrol, it has 6 wheels".
Before this Dekatron came back to life, the title of being the oldest working digital computer was held by NS1978. On hearing that it lost that coveted title, it got despondent, got drunk and was seen stumbling through traffic on the Jersey Turnpike, screaming out what time each driver will get home.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I was going to post an amusing personal coincidence from wikipedia: "the machine became operational in April 1951. It was handed over to the computing group in May 1952."
It's exactly one year older than me; I was born in April 1952. Whoever did the summary isn't very good at math, I'm not 70 years old. This thing was operational 61 years ago. Most of you guys grew up with computers, Computers grew up with me.
It is still a digital computer (as opposed to an analogue computer), as were other non-binary false starts like the Setun which used balanced ternary.
Yes, a base 3 computer would use positive, negative, and off. Seems like one would be a lot more complex to design than a binary computer.
They also had pure analog computers well into the 1960s (maybe even '70s) that used voltage as a "number system". Most were vaccuum tube based. No rounding errors, but noise was the problem.
Free Martian Whores!