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Report - Bletchley Park - The (System) X File

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28DL Full Member
28DL Full Member
Firstly, if you've never been to Bletchley, to say it's a bit bleak might be an understatement. If you venture out from the station, in search of - say - people breathing, you might be disappointed. There's some underpasses, and, erm. Well, that's it.

One night me any payno were there, we asked a local if there were any decent pubs. He laughed. But then - and I expected him to give us the local nod. You know... "but no seriously, if you go down there...".

Nope. He stopped. His eyes rolled upwards, thinking. Then, after about 30 seconds. He said... "no. no there aren't any. good luck. ". That's Bletchley.

But of course, there's Bletchley Park... home of all sorts of military cleverness from times past. Our first visit wasn't entirely unsuccessful, but it wasn't a proper explore. We'd found a "way" into the park and had a nice wander around. There's a Harrier in there, assorted old military buildings, and even better, a model railway (I'm still, slowly, tapping into payno's clearly secretive railway fetish ;) )

Roll on a few months. We're at a loose end. Payno suggests we go back. "There's another bit, something we didn't discover last time". A few quid in a cab, and we're trecking along a very poorly secured perimeter. Inski! It takes a bit more prodding around, but before us we've got a whole load of grim looking WW2 era buildings. Prefabs, almost. Boarded to buggery and due for demo.

When you see something like this, you just think.... bet there's nothing in there. And, by and large there wasn't. I was photographing anything. Stairs (hmm, ok). Peeling paint (oh no). Dust. My fingernails. Air.

Payno can do this on, what for me, is the most dull explore ever. And, after her processing, it'll come up smelling of roses. Ones that would win the chelsea flower show. I'm reasonably sure, if I shat a big pile, her shots would make the turds look polished. There's times I want to throw my expensive camera away and give up - but I've got a better option. Smash her camera up and run away. It would work. For a bit, perhaps.

So I console myself in a very simple way. Drink cans of stella. Usually works. And when you get really lazy, find some steps and have a nice sit down. And I did. Got me smokes. Got me beers. And all there is behind me, on the steps, is.... files... all marked for destruction a few decades ago. Might aswell have a look through... shiiiit... shiiiiiiit... this shouldn't be here. Fucking jeez...

...more to follow :thumb
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28DL Full Member
28DL Full Member
Re: Bletchley Park - The (System) X File - REPORT

Firstly, I should warn you. If you're expecting something about aliens, or secret submarines, or indeed the national steam reserve, switch off now and put a note in your diary to kick me at the next piss up for raising your hopes. But if you're a bit geeky about comms, you might still be interested...

This part of Bletchley park was, in it's final days, being used by BT. Some of it appeared to be labs, some of it training. It dated from around 1980 - there was still signage up with the old Post Office branding, and even a casually added "BT Share Price: " annotation on a whiteboard, suggesting it closed whilst the fever about BT shares - the first ever mass public share ownerhsip - was still running high.

Now let's rewind back to the 70s. Those of you who are old enough will remember the old rotary dial phones. The ones that went clicky-clicky and took forever to dial with. (Whoever decided 999 was our emergency number clearly hadn't thought it through ;) ). The switching system was literally a bunch of rotating mechanical switches - each would rotate as the "clicks" came through from the dial on the phone, making a series of physical connections across the country, before finally reaching your aunt doris in scunthorpe or wherever.

Then, in the late 70s, the post office had a vision. To leapfrog even the US (who had touch tone phones for some years by this point - remember the Rockford Files intro?) and develop the world's first fully digital telephone system. The system was developed with GEC, Plessey and STC - and was first unveiled to the world at the Telecom 79 exhibition in Geneva. In 1980, the first system was installed in the UK, and in 1990, the last electromechanical exchange was decomissioned.

In making this final step, the UK was the first country in the world to deploy an entirely digital telephone system. Amazingly, the system is still used today. Nearly 30 years later, and only now is it finally being replaced. The system, of course you've guessed it now, was called System X.

So, there I am on the steps. Rooting through the files. There were several national projects... conversion of coin boxes, and many other probably important things, but were far too technical for my eye. Then I found... "System X - Development and Export". It was the only file in the heap marked "In Strictest Confidence".

Inside there was correspondence at a very senior level - from the MDs of the various companies, and at one point the Department of Industry. The file was clearly not the whole story. It charted a small period mid 1980, but nonetheless a seemingly critical one - the build up to the first deployment.

Pics to follow :)


28DL Full Member
28DL Full Member
OK, back with you...

In 1968, the Post Office - then responsible for the UK telephone system - decided to plan for a major change to how telephone calls would be handled and routed, throughout the country. The plan was for a technology that would last two decades - the 80s and the 90s.

At that time, the system was electro-mechanical. The system worked, but was slow, difficult to expand and unreliable. If you grew up in the seventies, you might remember - if your parents moved - just how long it took to get a telephone line. Everything you could imagine russia ever was, but here in Britain.

At one point, we had a "party line". You shared a line with a random neighbour. If they were on the phone, you had to wait. Politely too - you could hear their conversation if you picked up the phone. The UK was running out of telephone lines.

What was need was a fully electronic system, but better than that, a digital one. Rather than having to grow exchanges physically - which was understandably difficult - instead thousands of lines could be processed by very compact equipment. Also, the equipment would be simpler to maintain and more reliable. A few processor boards could replace a rack of physical switches.

In 1977, the commercial partners were appointed by Post Office Telecoms. GEC, STC, and Plessey.

The project, was, of course, System X.

And here's the discovery of one of the key files:


In amongst the files there were bundles of tags, used for marking files for destruction. Each had an expiry date - by which time the related file should either be destroyed, or reviewed for a potential stay of execution.

It's difficult to imagine that the System X file would ultimately have been marked for disposal. The correspondance inside is at the highest level. From the respective MDs of the partner companies, and indeed, on one occasion the Department of Industry. And this is sat in a stairwell in an unremarkable abandoned building in Bletchley.

Some of the partners...



possibly one of the coolest logos ever :)


STC, were a minor player. What is missing here is GEC - who were 40% equal with Plessey.

So, into the file. Here's the front cover, in detail. To begin with things are at the level you might expect. Although it's high level people, many of the difficulties of the project - in such a short timeframe - are mundane. Initially ;)


Strike at GEC:

"when the staff finally realise the company means what it says and they will not be paid."

The charm of old-school industrial relations ;)


Now for a technical turn. A few moons ago, although not many, someone figured out you could make things bigger, faster, by lumping bits together. Computers, processors, that kind of thing. Why build bigger ones, when you can take a bunch of them and connect them up? It sounds blindingly obvious, but clusters are still a rare implementation. They're difficult to get "right", even with big companies like Microsoft investing millions in making them a product.

But back in 1980, there's this question...


and this answer...


It's only the first sentance or so that's important.

They believe they are first people to have discovered clustering. Now whilst half of you nod off, understandably, this is - to use a dreadful metaphore - like figuring you CAN go to the moon, if only you use multiple rocket motors. They can quadruple throughput. Even more. 100 thousand calls per hour becomes half a million. Glue a few more units together and the numbers grow in a linear manner.

This was an important thing for System X. You could just keep bolting on board after board - and it would still work. Goodbye having to queue for months for a phone line. Goodbye russian type service industry. Goodbye having to wait for those fucks (we never knew who they were), to get off the "party line". ;) Phones on demand. Whoda thought?

And indeed, here's their numbers...


Woodbridge - near the main R&D base at Martlesham Heath - was the first local exchange where System X was deployed. Here's the first mention in the file...


In between this, and the next extract, there is some wrangling. Plessey haven't been paid, and the MD is pissed off. The Post Office MD attempts to appease, but - at least financially - things are strained.

But then there's a very different issue.

There was an ambition with System X, to sell it to the world. It wasn't just meant to revolutionise the UK's comms, it was meant to change the world. And make alot of money in the process.

At one point though, some US outsourcing becomes a problem. Target markets - China and Russia - might fall foul of the US Govt...


Time to enlist help. Including the Department of Industry (DOI)... who later turn out to be as much foe as friend...


The DOI wants a chat...


I've worked on projects before - although nothing of course on this scale. But you get to know certain aspects of communication. If someone asks for a review, and they're a little bit senior to you and mighty pissed off, that's one thing. When they are very much senior, and incredibly polite, that's the time to start brushing up the CV.

If it was me, working on this, the penultimate line would be a killer...

(from the DOI, by the way)


In terms of any significance, the file begins to run out of steam out here. The ambition was to conqueur world markets. A vision to bring a new digital technology not only to the UK, but to the world, and in doing so, cement british companies like Plessey and GEC on the world stage for Telecoms...

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28DL Full Member
28DL Full Member
Re: Bletchley Park - The (System) X File - REPORT


In terms of UK success, System X was resounding. Post Office Telecoms had evolved into BT. And although BT - with shareholder responsibility - was subsequently required to seek competetive solutions, System X remained the preferred choice. In 1984, BT spent £300m on System X. By 1991, they had spent three billion pounds. And they continued to invest, to complete the total switchover to digital. By 1995 they were done.

Not only that, but remember the little snag with US embargos? Well, System X sold to America. And China. And Russia. And a bunch of other countries.

But in many ways it was too little too late. When the Post Office revealed the prototype in 1979 in Geneva, it might have had a chance. By 1981, after management and technical difficulties, the world had caught up. Alcatel in France, Siemens in Germany.

In the end, System X never made it on the global stage - at least not to a level where they could compete. Industry analysts expected it to play out between maybe three or four players. The UK was ranked 8th. GEC and Plessey merged their telco arms. But they were fighting a losing battle. In 1991 600 staff were laid off at Plessey in Liverpool. Ten years later, with more redundancies, from a workforce of 5,000 on that one product, there would be none. Plessey's merseyside Edge Lane plant was no more, and very soon, so was System X.

In 2003, it was "last orders".

BT, and the various countries using System X had one last chance to stock up. A 'handover' company was appointed to service the bitter end. From there, all that was left was service contracts. An innovation that had pulled in over 5 billion pounds for british tech industry, was down to 20 million a year - installing software upgrades, fixing hardware. After several decades, during which it acquired the likes of the british arm of Ericsson, the UK was finally wiped out of the serious telco hardware market.

But, despite the failed global ambitions, System X is still significant. We were the first country in the world to implement a fully digital telephone system. In many ways, ISDN and some of the building blocks of broadband were built on it.

Even today, the chances are you are making your landline calls on System X.

Not bad for 1979. :thumb
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28DL Full Member
28DL Full Member
Paulo, you've just suddenly dragged up a whole load of memories for me: Back in the mid 80's I left skool and went to the local tech to study mechanical/electrical engineering, during the course we had to pick an exsiting part of industry with emerging technology and write a Pros/Cons report about it. I chose telecoms and did a comparison between the old rotary system and SystemX, including takling to various members of BT and thier assoceates, my report was considered one of the most unusal and high scoring of the year group, as most of the year group had chosen to look at production line modification as we have a car plant not to far away!!!!
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