[a-dub]

i had the opportunity to visit bletchley about sixteen years ago... one interesting detail was that all the colossus machines were destroyed after the war as they were seen as too powerful and dangerous. it wasn't until years later that the retired telephony engineers (this was where ee excellence lived at the time) who had built them began rebuilding them from memory as a sort of hobby/club centered at bletchley. there used to be a fellow there named tony sale who would tell you all about it, but unfortunately he passed away a few years ago.

super interesting place and worth the short trip out of london! also i believe the term they used was "semi-programmable digital computer." bombes were mechanical search machines that i believe operated on short ciphertext sequences and i believe the big innovation with the colossus was having the ciphertext live on a long optical tape that would be re-read at thousands of characters per second, thus enabling a high speed processing loop of longer sequences. but i am no expert on this!

[PaulRobinson]

Tony Sale saved Bletchley Park. He was the instigator of the foundation and basically ran it single handed for a while. He believed deeply in it being preserved for the nation.

His main claim to fame before that was being Peter Wright’s right-hand man. Wright’s “Spycatcher”, talks of their joint exploits over the years. I got to ask Tony about it once, he was not too impressed Wright had done what he had done by writing that book.

[davejagoda]

Tony Sale still has an active website: https://www.codesandciphers.org.uk

[youngtaff]

They weren't all destroyed, some were moved to what became GCHQ (UK's equivalent to the NSA)

See Influence and Fate: https://en.wikipedia.org/wiki/Colossus_computer

It's Tommy Flowers I always felt sorry for, after the war he wanted a loan to build a computer was refused on the grounds that what he wanted to build was impossible. He knew it was possible but couldn't disclose that due to secrecy laws

[parpfish]

that's where they computed numberwang, right?

[cadr]

It was a huge advancement. Previously they were computing numberwang on slide rules.

[cryo32]

That's wangernumb!

[tialaramex]

ǝʇᴉsqǝʍ ǝɥʇ ǝʇɐʇoᴚ

[tetris11]

The National Museum of Computing (just up the road from Bletchley Park) has a working Colossus

[tialaramex]

I don't think I would describe the NMC as "just up the road". It's the same physical site.

If you consider the NMC "just up the road" then the Bletchley Park site you're thinking of is also "jump up the road" from er, Bletchley Park, a stately home that's less interesting to a nerd than either the NMC or Bletchley Park museum about war era "intelligence" but might be fascinating if period furniture is more interesting to you than the world's first (for many different values of first, the museum has several options, but not all of them) programmable computer.

[a-dub]

the nmc is most interesting, but also pretty cool to see turing's office in hut 8 (i guess the portable classroom like structure for a computer lab is a trope that goes all the way back to the beginning)!

[a-dub]

that's what i was describing! :) it's on the bletchley site (they share a parking lot) and was where tony sale and friends rebuilt the colossus.

although i just looked. critically they have different ticket offices. it was a long time ago! either way, worth a visit of both and they make up an excellent way to spend a day.

[KineticLensman]

It's on the same site but there is some institutional nonsense that means getting onto the Bletchley site doesn't guarantee access to the NMoC, which is only open on Tuesday, Thursday, Saturday and Sunday.

Don't ask me how I know...

[kps]

> telephony engineers (this was where ee excellence lived at the time)

Same in the US. It's why computers live in 19-inch racks.

[analog31]

Indeed, and why a lot of hi-fi gear was in 17 inch width, which was 19 inches minus the two one-inch rack ears.