UK's Oldest Computer To Be "Rebooted"

Smivs writes with this interesting piece of computer history, excerpted from the BBC: "Britain's oldest original computer, the Harwell, is being sent to the National Museum of Computing at Bletchley where it is to be restored to working order. The computer, which was designed in 1949, was built and used by staff at the Atomic Energy Research Establishment in Harwell, Oxfordshire. It first ran in 1951 and was designed to perform mathematical calculations. It lasted until 1973. When first built the 2.4m x 5m computer was state-of-the-art, although it was superseded by transistor-based systems. The restoration project is expected to take a year. Although not the first computer built in the UK, the Harwell had one of the longest service lives. Built by a team of three people, the device was capable of doing the work of six to ten people and ran for seven years until the establishment obtained their first commercial computer. 'We didn't think we were doing anything pioneering at the time,' said Dick Barnes, who helped build the original Harwell computer."

UK's oldest computer?

[solevita]

I thought that Colossus would take this title? Not only is it older and British, but it's also (I'm told) the World's oldest electronic computer [picotech.com].

Original Punch Cards too?

[realsilly]

For many of the younger generations of developers who don't know anything about these machines, it would be quite something to show them how the original developers used to work. It will also show how far we have advanced.

primitive pr0n

[syntap]

We didn't think we were doing anything pioneering at the time

Yeah, that's what the ASCII art inventors and the creators of GIF at CompuServ said.

computer, versus stored program computer, versus..

[Ancient_Hacker]

There's the problem of deciding what's a real computer-- do you include things that can crunch numbers, but have a hard-wired program, or have a program, but it's on a loop of paper tape, or have a program, but it's wired onto a plugboard. The Harwell machine is programmable, but the program is on a loop of paper tape, making anything other than one simple loop very problematical.

Also its data storage is in a few cold-cathode Dekatrons, which are basically overachieving neon lights. They limit the counting-up speed to about 20,000 increments per second, just barely in the electronic realm, and much slower than anything using real vacuum tubes. And it uses a lot of mechanical relays, further limiting its speed and making it a very marginal computer in any modern sense of the word.

Re:hindsight

[thisnamestoolong]

Saying that technological growth is slowing down or speeding up is total hogwash, in my opinion. The only way to measure technological growth is by placing arbitrary mile markers in the road. On one hand you have the folks that choose to measure technological growth by new inventions and can say that we are just polishing things that have already been invented. On the other hand, you have the folks that measure technological growth by its ubiquity, and show that more and more people are using more and more tech each year. Who is right, and who is wrong? I would submit that it is irrelevant and simply humans trying to place arbitrary classification on a complex system. We ought to just make sure that we are always doing our best to further the fields of science and technology, and not worry about whether our growth is faster or slower than in the past.

Re:Vaccum Tubes?

[rubycodez]

the thing uses dekatrons (ten cathode tube where pulse on guide electrode next to a cathode makes conduction jump to next cathode), which though not produced anymore are widely available. A computer made from them is much like a mechanical cash register with counting wheels. they are used by many hobbyists for clocks and other counting applications. no problem getting them

Re:Obligatory tired meme

[JCCyC]

I'm more interested in having it emulated in MESS [mess.org].

Re:A joke my Dad told...

[svtdragon]

My mother owned a Jaguar X-type from 2002 or so. I once read a review of it (this one [automotive.com], I think) and they made exactly this point:

There was a time not long ago when Jaguars were stunningly beautiful, fantastic driving cars that were known to be fragile and unreliable. Jaguars were sexy but leaked oil. Jaguars were luxurious and emotional, but their windows often failed to go up or down. Jaguars were invigorating to drive but could leave you stranded on a cold morning.

This Jaguar, the X-Type, is the opposite of those great Jags of the past. This car trades those wonderful qualities that made Jaguars cars to lust after and has replaced them with the bland reliability that makes Toyotas cars to lust after....

Maybe we'd like it better if it leaked.

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[account_deleted]

Comment removed based on user account deletion

Manchester Small-Scale Experimental Machine, 1948

[davidwr]

The Manchester Small-Scale Experimental Machine [wikipedia.org], aka the "Baby" Manchester Mark I, ran its first program in 1948. A replica was built in 1998 to celebrate its 50th anniversary.

It had 32 words of 32 bits each and used a Williams Tube [wikipedia.org] for memory.

Opcode list:

000 JMP S Jump to the instruction at the specified memory address (absolute unconditional jump)

100 JRP S Jump to the instruction at the specified memory address plus the number in the accumulator (relative unconditional jump)

010 LDN S Take the number from the specified memory address, negate it, and load it into the accumulator

110 STO S Store the number in the accumulator to the specified memory address

001 or
101[t 1] SUB S Subtract the number at the specified memory address from the value in accumulator, and store the result in the accumulator

011 CMP Skip next instruction if the accumulator contains a negative value

111 STP Stop