Editor’s Remarks

On holiday in darkest Lancashire I stepped into a local Co-op in search of mushrooms. The shelves, whilst far from bare, revealed no trace of mushroom. I made enquiries. The staff were most obliging and explained that they had just received a delivery and that they might be able to help. Emerging from the stockroom with a folder full of lineprinter paper detailing the content of the day’s delivery, they soon had me on my way, mushrooms in hand.

But I was moved to observe that I hadn’t seen proper lineprinter paper, full width, sprocket holes, impact printed, fan-fold, the whole nine yards, for years and years. Something we all once took for granted as a part of our professional lives has almost disappeared without me even noticing. The very word “lineprinter” is unknown to Microsoft Word. I wonder what else has gone while I wasn’t looking?

In this edition our Pioneer Profile stretches the meaning of that title. But, even if you feel that Brian Warboys might be too young to qualify as a pioneer, there is no denying the importance of his leadership of the development of VME: the last great mainframe operating system. Still in widespread use today, almost four decades on, it wears its years lightly. But in case you wanted something from earlier times, Tony Hoare’s scintillating account of his Elliott years can come to your rescue.

Society Activity

Software Preservation - David Holdsworth

The Software Preservation WP is going hard at resurrecting Whetstone Algol for KDF9. We have copy-typed the translator, and run it under emulation with considerable success. The state of play tends to be reported publicly to sw.ccs.bcs.org/KDF9.

The story is of one heroic typing efforts, scepticism on the part of Brian Wichmann (the project’s originator), then the discovery using an assembler written in yacc and C and two emulators, that we really do seem to have achieved an accurate (perfect?) reconstruction of the binary program from a lineprinter listing. It is now possible to download an emulator and the KDF9 binary program and have it translate Algol 60 programs but not yet execute them. By the time of Resurrection 48 hits the stands, we should have that up on the website.

Manchester Baby - Cat Rushmore

Redevelopment of the reception area at the Museum of Science and Industry (MOSI) will result in a rest for the Manchester Baby replica. The machine will be removed from its current position around mid November and put into storage. It is anticipated that August 2010 will see it reinstalled in a still more prominent position at which time the weekly demonstrations will recommence.

ICT 1301 - Rod Brown

Short term aims:-

The addition of extra drums is now complete and the additional storage will be phased in to raise the existing 12,000 words of store first to 24,000 words and then up to 36,000 words. This last figure relates to a storage capability of 216,000 bytes of online store.

At the annual open day on 12 July, we greeted 320 visitors. We have now delivered five open days to date and counted over 1305 visitors. Further details of the event and all of the news from the project are covered on the dedicated website at www.ict1301.co.uk.

The annual open day was almost cancelled by a short circuit within the CPU. As a result the project status has slipped from 93% to below 85% after this burnout damaged many printed circuit boards in more than one of the logic cabinets. The problem was resolved just two days before the event and the machine delivered over seven hours public running on the day.

After this major setback to the machine’s reliability, work continues to recover this lost ground and to reach our primary aim of software recovery.

Project activities:-

The 1301 project has placed further machine manuals online, so the Initial Orders manual joins the Programming manual as a download from the project’s website. A further four manuals covering standard languages will follow as they are prepared.

At least two card pack images will be added to the online files. These will be available as both card binary images and ASCII card images. Both packs are provided to allow a deeper understanding of how the machine was programmed and complement the current published technical and system programming information.

Anyone wishing to contact the project or to arrange a visit should use the email buttons on the project’s website. We promise that all contact will be responded to.

A new home for Arthur

The third aim of the project was to find a new home for the other 1301 machine which was housed at the project. After many years of trying to find a new owner who would grant public access to the machine, we can now report news of interest to all members of the CCS about a new Computer Conservation Project and website.

Late in 2007 the 1301 project started attracting individuals who were seeking a means of sharing active conservation skills and exchanging knowledge. The resulting cooperating group has resulted in many existing projects that were working in relative isolation helping each other to resolve problems, share information and even recover the contents of historic media from one form of storage to a more modern medium.

I am proud to note that the following new computer conservation website has joined the growing family of cooperating webmasters and system owners who, by their own efforts, are promoting both active conservation and the sharing of the historic knowledge base, whilst raising the interest of visitors.

Here is a quote from the owner “Our aim is to try to put that spark of curiosity about innovation into all the visitors especially younger children who are, after all, tomorrow’s engineers and scientists”

So visit t-lcarchive.org, a new multi-system site for a private museum. See for yourself just what these dedicated system conservationists are doing, focusing on the northern end of the country, and designed to catch visitors’ interest in conservation and history.

Oh and by the way, this is also the new home for “Arthur” the only other surviving 1300 computer system left in the UK.

Pegasus

Worrying news from the Science Museum, a statement has been issued concerning Pegasus.

“On Wednesday 29th July 2009 there was a small electrical fire in the Pegasus computer during its demonstration by CCS volunteers. As a result of the incident all demonstrations of the Ferranti Pegasus computer, and the 401 working party at Blythe House, are currently suspended. The museum is conducting a formal investigation into the actions of staff post incident, the management of hazards, particularly asbestos within the Museum’s collection, and the supervision and training of volunteers. At the end of this investigation a report will be completed, so that NMSI management can have complete assurance that any future activities of the CCS or other operators are planned, operated and supervised within legal requirements of Health and Safety and NMSI Health and Safety policy. CCS volunteers are thanked for their patience and cooperation during the investigation and in the implementation of its outcomes.”

The CCS website will be kept up to date with news as it arises.

The Pegasus Story: a history of a vintage British computer

On a more cheerful note, December 2009 marks the 50^th anniversary of the Science Museum’s Pegasus computer. As well organising a celebratory event next spring, we are investigating getting the excellent book about Pegasus available again. The first edition was published by the Science Museum in 2000, but is now out of print. The book provides more information for visitors and for people interested in computer history.

The book was written and researched by CCS’s Simon Lavington and communicates the significance of Pegasus in UK computer history - including its relationship to preceding developments. It is well illustrated and authoritative. The Science Museum has asked the CCS to investigate producing a second edition.

We have located the original publishing data files and got samples produced on today’s printing technology using a “Print on Demand” system. We hope to publish the second edition and launch it at the CCS Pegasus event next year with an expected introductory price of £7.50.

The book will be similar to the first edition (64 pages in B&W with 28 photos, and many tables) with updates and amendments.

We hope that readers will support this initiative by ordering copies in advance so that we can recover the setup costs from an initial batch of sales to CCS members. With the agreement of the author, the aim is that all net proceeds will go to the CCS to help to maintain and demonstrate Pegasus.

Look out for more details on the CCS website in due course. Please contact (or ‘phone 01344 422993) if you wish to support this project and to reserve a copy now.

Branching out

For the first time, the Society is arranging a lecture north of the border jointly with the Edinburgh Branch of the BCS. A repeat of the JANET lecture from earlier in the year was scheduled for 22 September and, if successful, may be the first of many. Scottish readers may also be interested in a lecture on Second World War codebreaking by Mark Baldwin. Details at www.edinburgh.bcs.org/events/2009-10/091209.htm.

Bombe Rebuild Project - John Harper

The good news is that our appeal for funds to complete the drums necessary to run German Navy Surface Fleet jobs has reached its target. The final components that had to be produced on CNC machines due to the large number involved have already been delivered and are now being assembled. We hope to have the full set of drums completed and ready to run jobs later this year.

I would like to take this opportunity to thank all those who made these very generous donations amounting to a total of £2,000. It is most gratifying to have so much support in these difficult times.

There is not much to report about the Bombe itself because running it has become a regular occurrence with few problems that cannot be fixed by checking all connections and the initial drum settings. The faces of the commutators appear to get quite dirty at times and need a clean but this is a quick and easy thing to do. It is thought that in spite of a great deal of cleaning we are still suffering from the protective thick oil that was used to protect the piano wire that we made into drum brushes.

Our most serious problem now is that we are asked to provide far more visitor demonstrations than we can handle. Our team was set up to rebuild a Bombe but not to run it on a regular basis. This was always expected to be a Bletchley Park Trust responsibility after a suitable training period.

We are therefore making an appeal for people to come and operate our machine; mainly at weekends but after a comprehensive training programme that the present team will provide. The level of capability a successful candidate would achieve would be similar to that attained by the WRNS Bombe Operators in WWII.

If you feel able to come and help, my email address in inside the back cover. Our website is still at https://www.bombe.org.uk/

News Round-Up

In this edition, our first and happiest task is to offer the congratulations of the Computer Conservation Society to Tony Sale who was recently awarded an honorary doctorate by the Open University in recognition of his work on the rebuilding of Colossus. To quote part of the citation - “Tony Sale is a gifted and creative engineer, but more than this we honour his great engineering achievements, his leadership and energy. Bletchley Park was a piece of history that nearly disappeared. The efforts of Tony Sale were key to the hard-won battle to keep it alive.”

In reply, Tony paid tribute to the Colossus rebuild team and to the original codebreakers.

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On 16 July 2009, The National Museum of Computing welcomed the Duke of Kent to the museum. His Royal Highness was shown the new PC gallery, and then taken to see the progress of the Colossus rebuild project which he inaugurated in 1994.

Prior to making presentations to Bletchley Park veterans, the Duke expressed an interest in seeing the Bombe rebuild project again, and John Harper kindly demonstrated the machine working. Both John Harper and Tony Sale were later presented with awards for their contribution to these projects that are such core components of the Bletchley Park story.

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The National Museum of Computing reported the arrival of a suite of 40 column punched card equipment in Resurrection 47. Work has progressed at a pace on restoring these machines to working order, but a problem common to much of this machinery has been found: sticky Bowden cables! Some of these cables are in excess of one metre long and the original lubrication has long since dried out. What is the best method of cleaning and lubricating these cables? Suggestions are welcome and should be sent to Graham at .

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The Science Museum is celebrating its centenary in various ways. A series of evening lectures by distinguished scientists are scheduled (dead hyperlink - http://www.sciencemuseum.org.uk/Centenary/Home/Whats_on.aspx). Unfortunately Tim Berners-Lee’s lecture has already taken place, but that by Professor Dame Wendy Hall of Southampton University on 23 November will be of interest to CCS members.

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Kevin Murrell has been researching a computer developed at Harwell back in the very late 1940s. The machine is generally known as “The Harwell Dekatron Computer” because of its use of Dekatron tubes for program and data storage. It later became known as the WITCH computer when it was donated to Wolverhampton College of Technology in 1957. It was used to teach computing in Wolverhampton until 1973 when it was donated to Birmingham Science Museum (see Resurrection 45). Kevin has interviewed the original designers of the computer, and some of the academic staff from Wolverhampton. The various components of the computer have now all been found and have been transferred to The National Museum of Computing amid much publicity. It is, of course, intended to restore the machine to working order and a new CCS Working Group has been set up for the purpose. When the restoration is complete, it will oust the Science Museum’s Pegasus as the world’s oldest working stored-program computer.

There is more information about WITCH at www.computerconservationsociety.org/witch.htm. In addition, Jack Schofield, writing in The Guardian (9 September) gave particularly good coverage. Kevin will be talking about the machine at our March meeting at the Science Museum in London

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The response of the UK government to the e-petition to “Save Bletchley Park” (21,920 signatures, since you ask) was less than fulsome, but happily, the future of the Park seems more secure now. As Resurrection went to press, £500,000 of lottery funding was announced.

A more recent petition to obtain an apology for the way the state treated Alan Turing in the 1950s (31,792 signatures and counting) has fared rather better. The Prime Minister has issued a statement in which he not only apologises, but pays generous tribute to Turing and the work he did at Bletchley Park. Overdue, but nonetheless welcome. The Daily Telegraph (10 September) carries the full text.

Pioneer Profile: Brian Warboys

In 1967 I had just returned from working on secondment at RCA and had moved into a new house in south Cheshire. One day there was a knock at the front door and through the glass panel I could see a dark hirsute shape. On opening the door there was my bearded, next but one neighbour, Brian Warboys. His current lift sharing arrangement had ended and he was looking for a regular lift into work. This was in the days when one car was almost a luxury let alone two and Brian’s teacher wife had priority on their only car. So Brian, my wife and I travelled to work together for several years, through rain, snow and the birth of several children! Although our later careers were to become closely entwined, at the time we were working on completely separate projects.

Brian comes from south London (he is still an unrepentant Millwall supporter) but was introduced to academia at a very early age as he has the distinction of having been born in Ruskin College, Oxford. As the beds in the London area were reserved for emergencies during the war, mothers were shipped to Oxford to give birth and then sent straight back to London. His father was signalman on the railways and the two previous generations had also been employed on the railways. Railways weren’t however his future as, having gone to Colfe’s Grammar School in Lewisham, he went on to do a mathematics degree at Southampton University. After three years, which was apparently dominated by playing rugby (and associated activities!) plus getting acquainted with his future wife, he got his degree and then gainful employment with English Electric based at Kidsgrove.

So in 1963 Brian started his computer career as a systems programmer working on the Egdon Supervisor (Operating system) for KDF9. He became part of a three man team whose total operating system experience was zero! Although the system was produced on time it still needed a good deal of “care and attention”, so Brian was dispatched to Winfrith for five months as on-site support. Such was his dedication to the task that the Royal Hotel in Weymouth is listed as home on his marriage licence!

Later he moved on to System 4/30, one of the early models in the English Electric range derived from the RCA Spectra70 which itself was derived from IBM’s 360 series. This particular model was not particularly successful being underpowered and not being fully upwards compatible with the larger and main models in the range. However it was here that Brian effectively left his programming career behind and began to get involved in the system design.

The next step was into “proper” operating system design! The Operating System for the main System 4 models was called J which was a multiprogramming batch system. However this was when interactive/timesharing systems were just beginning to be developed. Such systems as MULTICS and Project MAC were opening up a whole new view of what computer systems could potentially do. Brian, along with Peter Cropper, was given the task of designing extensions to convert J into a system capable of simultaneously supporting several interactive terminals. They produced the design for Multjob. This proved to be an interesting and challenging job! It should be noted that this was for the System 4/70, so they did not have the benefit of a hardware-based virtual store system, and only limited hardware support for programme relocation. In particular, the relocation of programmes containing I/O command chains required special treatment. This was Brian’s last ever professional coding task. He wrote a small routine for dynamically relocating command chains which was not as simple as it might first appear given the fact that they could contain branch instructions to anywhere in the programme, a facility that I had enthusiastically exploited in my work on Indexed Sequential. This issue was the subject of several conversations during our journeys to and from work!

By the end of the 1960’s ICL had been formed and the need to rationalise the range of machines and systems was high on the agenda. This resulted in the start of New Range, a project to specify all aspects of the future range of ICL machines and systems. The team was made up of people from all parts of the company. Brian and I were seconded to the activity, as representatives of Kidsgrove/System 4 software. So for nearly two years we spent three days a week in Putney and two in Kidsgrove.

The New Range activity looked at all aspects of the system covering I/O, communications and software as well as the central processing system. This central machine architecture was really the output that characterised New Range. It was one of the first systems to fully enable virtual addressing for system software as well as having a machine code and addressing architecture that enabled in-process as well as out-of-process data protection. It was this area that Brian worked on.

Another output of New Range was the definition of a family of Operating Systems (VME/A, B, C etc) specifically aimed at particular capabilities. VME/B (the general purpose system) was allocated to Kidsgrove and Brian became its lead designer. He was, however, much more than an operating system designer. He established a design philosophy where architecture was king (much to the frustration of some future marketeers who wanted short-cut designs “now”!), a design team (OSTECH) that became the keeper of the philosophy and a dynasty in its own right and a development methodology (CADES) that has much to do with the system’s continuing longevity. The strength of these three areas was that they were conceived as a coherent whole and were the basis of why the system was able to absorb the fast changing hardware technologies and outlive the other systems identified in the original New Range specifications.

It was during this time that another of Brian’s strengths came to the fore. To say we were living in “interesting times” was to put it mildly. The upper echelons of ICL were not exactly stable for much of the early life of VME/B with the arrival of the Americans and their subsequent departure and replacement. It was here that Brian’s political as well as persuasive ability were brought to bear as he steered us through the various challenges that came our way. In particular he was highly adept at explaining to the newcomers why VME/B was right and exactly what they wanted and while it’s not clear that they always understood him, they definitely went away thinking that they did!

In the late 1970s Brian moved on from VME to take up a wider role at the divisional level which was to lead to the next significant stage in his career. This wider divisional role included systems design methodology and this led to contacts with the University of Manchester Computer Science department. This relationship soon developed and Brian took on a role in the department as a Professor of Software Engineering being half time between the university and ICL. At this time (1984) he was also appointed as ICL’s first Fellow.

Brian had previously had contact with the University during the NR secondment when he was involved in possible MU5 convergence. There was a long history of ICL/Manchester collaboration going back to soon after the University developed the world’s first stored program computer in 1948, in particular an industrial alliance with Ferranti who developed a number of the University’s research machines, most notably the Ferranti Mark 1, Atlas and MU5/2900. Brian’s appointment was yet another part in the long line of ICL/Manchester collaborations.

Brian used his ICL Fellowship to champion the role, status and impact of the technical community across all of ICL. Initially under his sponsorship an additional five Fellows were appointed (this number was added to over the subsequent years). The Fellows regularly had informal meetings with the then ICL CEO (Peter Bonfield) where they could give their views/question Peter on any subject they wanted. Out of these meetings came a further scheme to develop the technical community which was wider than the Fellows, the appointment of Distinguished Engineers. The DE scheme became a valuable network for the technical community that cut across the (continually changing) organisational structures.

Brian remained half time until 1995 when he left ICL to become full time at the University. Initially his main academic interest developed from his experiences on VME and CADES and in particular the problems of designing very large software systems. The scope of this work gradually expanded to include dynamic evolution (the ability to change software whilst it is executing) in the design of very large systems as well as the application of Process Modelling in the context of the organization. The work was done as part of several national and multi- national research projects and was a significant contributor to the department getting a five star rating in successive RAEs.

Finally he retired, or at least became an Emeritus Professor, in 2007 so he could spend more time with his grandchildren and his golf clubs. Notwithstanding his University work his undoubted legacy is VME. VME made a major contribution to ICL’s coffers, is still in use today in systems which impact us all (e.g. the Inland Revenue) and is a near perfect example of how a well architected system can exploit unpredicted future technology and respond to evolving business demands.

NATS Air Traffic Control Restoration at TNMoC

In Resurrection 45 we read the news that the former London Air Traffic Control System was up and running at The National Museum of Computing at Bletchley Park. The full story of how it was restored to health is what used to be called “a ripping yarn”.....

NATS Central Computer Suite

3:15pm on Saturday, 26 October 2008 was both important and exciting at The National Museum of Computing. It was at this precise time that over six months of work by Ben Trethowan and Peter Vaughan finally paid off with two large green bug-eyed displays showing something other than “Display Frozen”. The National Air Traffic Services (NATS), London Area Traffic Control Centre (LATCC), Air Traffic Control (ATC) Radar system, originally based in West Drayton, was now displaying details of flights around London Heathrow from a test recording made on 14 March 2003.

The system is one of the last remaining PDP-11 based Radar stations used at West Drayton and was installed there during the 1970s. While the Museum was promised this equipment some time ago, it took many years before it was finally decommissioned and was made available to the Museum in February 2008, just before West Drayton was bulldozed.

The complete system comprised:

• A Walton Radar record/replay unit using DAT tapes,
• A 24 track reel-to-reel record/replay rack mounted tape deck,
• A Newman RK05 SSD (Solid State Drive),
• Two DEC PDP-11/84s,
• Two DEC PDP-11/34s,
• Two desk stations each containing a large round green radar screen.

The Radar Screens

The start-up sequence was quite involved... The Walton replay unit was started, the DAT tapes loaded and system set to replay mode. The operating system and maps were then loaded into the Newman SSD from a 21MB floppy drive. Once loaded, the first PDP-11/84 (called an RBEG) booted from the Newman and controlled access to it for the other units. Once the RBEG was booted the second PDP-11/84 (called the BEG which processed the radar data) was booted from the Newman via the RBEG. Once the BEG was booted, the two PDP-11/34s (called DEGs) were booted from the Newman via the RBEG each controlling one of the big radar screens. Once they were all loaded, aircraft positions replayed by the Walton unit were passed through the RBEG to the BEG, processed by the BEG and passed on to each of the DEGs to display on the radar screen.

The Restoration ... (Walton Record / Replay unit)

While most of the system had been operational up to the end of 2007, we discovered soon after it was delivered that the Walton Replay unit was not actually used with the PDP-11 equipment we had. Whilst we were supplied with a full set of manuals on the PDP kit, we had nothing on the Walton replay unit or any cables to connect the two together. Also, initial testing of the two DAT drives indicated one had a fault and would not read any of the recorded tapes supplied with the system. This was the first hurdle to get over.

I spent two weekends trying to source a replacement DAT drive, an Exabyte 8205S 5/10GB, originally sold in the early 1980s. We did not get a spare with the equipment as far as I could see and, after scouring other equipment in the Museum, I finally found a later but read-compatible drive in our workshop. With this fitted we could now read the supplied tapes. The next hurdle was how to connect the replay unit, which had 96 nine-way D-Type connectors, to the PDP- 11/84 RBEG unit which was expecting two separate BNC connections for clock and data.

Using an oscilloscope and a process of elimination, I determined that each nine- way D-Type had four pins with signals. One appeared to be a regular frequency (clock maybe) and the other three had changing frequencies (data maybe). Because the Walton unit was never actually connected to the RBEG before, it was not known if its RBEG serial card required TTL RS232 levels (± 5V) or whether it could handle the normal ± 12V levels that were being supplied. We decided to check the RBEG PDP-11/84 and took out some of the cards. It was not obvious from the cards what the signal levels were because it was using a non DEC serial card so we assumed it would be fine and put the cards back in, in what we thought was the original locations - see later. I made up a suitable nine-way to BNC cable and a suitable adapter so I could check each of the data pins to see which ones worked as clock or data We were supplied with a radar data test box so, after some further trial and error, I eventually discovered the correct pins and the test box was seeing valid radar data. Our first hurdle was behind us; we had a working replay unit and some data to play with.

Error 77... Error 77... Error 77...

That done it was time to turn on the PDP-11s, which Ben had previously had working shortly after they arrived, but without any data feed from the Walton unit. “Not long now before we get something on the big screen” we all thought. We switched on the Newman SSD drive and it loaded from floppy. “Looking good” we thought. Next we switched on the critical RBEG PDP-11/84 without which nothing else would work. It did not start but reported error 77 on the LED panel. Now we had a serious problem.

Knowing we had removed some of the cards the previous weekend we had a look at the failing PDP-11/84. Error code 77 indicated a power supply unit (PSU) fault. After many hours of reseating cards we did some tests on the power rails and discovered they were way too low. We then suspected the PSU had failed. We had a spare so the following week I changed the PSU (this was my first time and it took about three hours) and tried powering on the 11/84 again. “Error 77”, it can’t be the PSU. We have several PDP experts in the museum so they spent several more weekends with us trying various things to get the PDP-11/84 working without much success. Then, after removing various combinations of boards to leave the bare minimum CPU and RAM, we eventually found that when a small board on the back bus was removed, the system got further in the start-up process. By this time we had contact with some of the original engineers who maintained these systems so we explained the problem to them. They had no idea what the small board was and concluded it should never have been in there. It is still a mystery now why it was there or how the system originally booted OK with it fitted when it first arrived.

Now we thought we had the solution so put all the other boards back, and switched the system on. It got as far as error 43 and stopped again. So we had a second fault.

Removing and replacing each of the boards in turn we eventually discovered what the problem was. The second fault turned out to be a result of having two cards in the wrong slots. One of the card slots had a special BUS grant link removed so a specific card could be fitted there - this was spotted by Kevin Brunt (thanks Kevin). It turned out (although we are still not sure how) when we originally put all the cards back after checking the serial cards several weeks earlier, we had somehow got two of the boards swapped over. With all the boards in the correct order the system finally booted correctly. Progress at last!

The Final Hurdle... We Tripped... We Fell

It was the BEG’s turn next, the second PDP-11/84. This was powered on. It loaded and started fine. We were on a roll! We then started each of the DEGs (PDP-11/34s), powered on the radar screens and finally got something displayed on the big green screens. That something was “Display frozen”, but it was progress. Now for the final connection! We connected up the replay feed from the Walton unit and waited for the data to appear on the screen. We waited... and waited... but nothing. We had another problem. But where? We knew the data feed was correct as the test box confirmed this. We knew the data was getting to the RBEG as it reported seeing data on the console, but nothing showed on the radar.

A further two weeks passed checking all the boards were seated and in the correct place, that the software was loading correctly and all the cables were plugged into the right place, but to no avail... “Display Frozen” was all we saw. We initially thought the radars were set to the wrong sectors for the data, we discovered how to set them to different sectors but it made no difference. Much head scratching and book reading occurred without any progress. We were so close but could not find out why nothing was being displayed. It was very frustrating.

All Hail the Paperclip...

Ben decided to go back to basics and checked that we had cabled everything up correctly once again. In checking one of the radar data feeds from BEG to DEG he noticed a broken wire - it had broken off inside the connector and was a black wire on a black connector, easy to miss. Further inspection found that two black wires were actually broken. We had another problem.

These were not your common or garden D-type connectors but some very old pin and socket connectors requiring a special tool, which we did not have, to remove the pins. These connectors are also normally crimped so we were stumped. We had no spares or any way to make up a replacement. We didn’t have the cable layout either but we had to find a way to fix it. I spent the next hour documenting the cable and asking various people if they had any similar connectors or a way to take it apart but the answer was no. I then inspected the connector in more detail and noticed some of the wires had solder on them. I then discovered this connector had the wires soldered not crimped - this is fixable I thought.... With a suitably hot soldering iron I managed to heat up the two faulty pins from the wrong end enough to remove the soldered broken end of the wire without melting the connector. I then repeated the heating and managed to solder paper clip wire into each of the pins. Five minutes later I had successfully soldered the two broken wires onto the paper clip wires (having worked out the correct pin connections earlier). Time for a test... I reconnected the cable between the DEG and BEG... it was 3.15pm... both screens filled with numbers and lines... we had done it!

The End? Well Err... No....

While the system is now working, the project is not yet quite over. We still have the magnetic tape deck to get working which was the original recording and playback method before being replaced by the Walton unit. However we have a problem with the magnetic tape degrading for which we need to find a solution.

We did have another problem which surfaced after several months of faultless operation. For some unknown reason the BEG processor would not load on power-up. The problem appeared to be a DZS11 serial card responsible for communicating with the RBEG. Over a period of two months we had six board failures. On further investigation we noticed none of the cabinets or PDP-11s were properly earthed and this was always a problem on PDP-11 systems I am told. Johan Iversen, one of the volunteers, added the necessary earth straps and so far the problem has not returned.

Although a lot of the work described above was done by myself and Ben, many others in the museum contributed to the success of this project along the way. It is the dedication of so many volunteers at the museum that has lead to many of the systems you see today being fully restored to working order and available for the public to see.

Editor’s note: Peter Vaughan is a volunteer at The National Museum of Computing at Bletchley Park. He can be contacted at . You can see the system working each Saturday at the museum. Visit www.tnmoc.org for pictures and videos of the system in action.

A Mystery Control Panel or Two

Atlas 1 Main Control Panel The hands are those of Tom Kilburn and Sir John Cockcroft

In Resurrection 47 we read about the reopening of the Museum of Computing in Swindon. Your chairman David Hartley and your editor were in attendance. As we looked around the museum our eyes alighted on an exhibit described as the control panel from Atlas, a photograph of which appears further below. Atlas men as we both were, we said together “No it isn’t. We know what the control panel looked like and this isn’t it. The Atlas control panel looks like that thing →!”

The museum volunteers were on their best behaviour. Rather than throwing us out, they engaged us in conversation. The provenance, it turns out, is impeccable. The panel was rescued from the scrap man by the late Alan Fairbourn then of London University’s Institute of Computer Science. He mounted it in a wooden frame and gave it a new life as part of the control panel for a model railway. Years later, Alan’s son Simon donated it to the museum.

We now think that it is an Atlas 1 control panel, but not the main panel. Was it, perhaps hidden away in a cabinet somewhere? So does anybody recognise it? The label “CORE STORE” gives a clue. What was it for? Where was it? The museum would like to know. So would we. So if you have any information please let us know.

The Mystery Atlas Control Panel

But as it turns out, we didn’t know as much about the main Atlas Control Panel as we thought we did. Kevin Murrell sent us this photograph of an object in the Museums Collection Centre in Birmingham which had us stumped for a while.

Main Control Panel from the CAD Centre Atlas 2

You’ll notice that it’s similar to, but not exactly similar to, the main panel shown at the top of this article. The toggle switches are obviously later, being the same as those found on ICT 1900s and the Ferranti Orion. The ICL badge also confused us for a while because ICL didn’t exist when Atlas was in production. But we think it’s from the Atlas 2 at the CAD Centre. The CAD Centre machine was in store for a few years after Atlas production stopped because ICT couldn’t find a buyer for it. It wasn’t actually installed until 1969, which accounts for the ICL badge and the later toggle switches. And, of course, being an Atlas 2 rather than an Atlas 1 would account for the differences in the buttons/indicator lights

The clincher however, was the card at the bottom. If you use a little imagination, part of it reads -

PRESENTED BY
COMPUTER AIDED DESIGN
CENTRE
CAMBRIDGE

Now why didn’t we think of that first?

My Early Days at Elliotts

Like many of us, Tony Hoare’s career in computing began by accident, though few of us can claim an accident as convoluted as his. Nor can most of us claim a career as distinguished. Great oaks.....

It was in 1960 when I first saw an Elliott computer, the 803A, on a stand at a public exhibition of British Scientific Instruments in Moscow. How did I get to be there? That is a story which I could tell you backwards. And what happened afterwards? That is a story I could tell forwards. Both of them are very long stories. I’ll start by going backwards. Then I’ll wind the tape forwards again.

Then - Tony Hoare in Moscow 1960

To start with, you have to know that my uncle Sandy was a Captain in the Royal Navy. (I told you it was a long story.) After he retired, he took a job as General Secretary of the British Scientific Instruments Manufacturers Association (SIMA). It was he who organised the exhibition in Moscow; he knew that I was a Russian speaker living in Moscow, and he thought of the idea of inviting me, on behalf of the Association, to act as an interpreter at the exhibition. He offered me £40 to do it, which I thought would be jolly useful when I got back to England.

My duties were indeterminate. I would translate questions and answers at the public lectures given by the exhibitors. I would do the same at an exhibition stand. When one of the exhibitors got appendicitis, and was cast into a Russian hospital with nobody capable of speaking English to him, I was able to give him a little bit of temporary comfort, I’m glad to say, and left my English- Russian Dictionary with him. For these and other services, the organisers gave me another £40 as a bonus when I returned to England.

The reason why Elliotts were at the exhibition was because of the prospect of selling their computer to a Russian customer when the exhibition was over. This was standard practice, no doubt to bypass the administrative barriers (on both sides) which hindered more normal trade across the Iron Curtain. And for the Russians it was a good deal. After a week at an exhibition, the computer became second-hand goods, and could be purchased at a generous 14% discount. Did they realise that this was exactly the amount by which Elliotts had marked up the price of the computer before bringing it to the exhibition?

How did I happen to be in Moscow at the time? I was studying as a graduate student at Moscow State University, on an exchange scheme sponsored by the British Council. I had chosen to study Probability Theory at Moscow State University, in the Department of Professor A.N.Kolmogorov, who was the distinguished founder of the subject. This was because in the previous year I had been studying for a Certificate in Statistics at the University of Oxford. In the two years before that I had learned Russian on National Service in the Royal Navy. In getting accepted by the Navy, it was helpful to have a close relative in the service, and an uncle who was a Captain would do nicely. Only the wildest vagaries of chance could explain the particular combination of circumstances that brought me to my first contact with Elliotts. The only lesson to learn from this long story is that if you want a long and successful career in computing, it helps to start with the right sort of uncle.

I have to confess that I was out of my depth in the mathematical study of probability theory at postgraduate level in Russia. So I was quite happy to be diverted from that subject by a letter that I received in Moscow from the National Physical Laboratory in Teddington. They offered me a post as a Senior Scientific Officer to work on a project just started for automatic translation from scientific Russian into English. They were writing a translation program in machine code for the Pilot ACE computer. My English companion at the University residence, Glyn Harding, was a real scientist, so I consulted him about the offer. He told me that Senior Scientific Officer was a very prestigious post, and I was very lucky to get the offer.

So I started looking into the state of the art in machine translation of languages. I looked as far as the Lenin Library in Moscow, where I first read a work by Chomsky on his context-free grammars; I didn’t understand it at the time, I’m afraid. The Russians too were interested in machine translation. In fact, they had a regular journal called Mashinniy Perevod - that’s Machine Translation - to which I submitted my first published scientific article. I wrote it in Russian, and I typed it up in Russian on a typewriter borrowed from a friend. It’s not very often attributed to me because my name was transliterated into Russian as “XOAP” with a ‘Ch’ at the beginning rather than an ‘H’ (which does not exist in Russian). When transliterated back into English, the name becomes “Choar” or possibly “Khoar”. So if you want to look up the article in the bibliographies, you’ll have to look under ‘C’ or ‘K’.

The first problem of machine translation that interested me was how to sort the words of each incoming Russian sentence into ascending order. Recall that the main stores of computers of those days were large enough to hold one sentence, but certainly not large enough to hold a dictionary. The dictionary was held on magnetic tape, so to look up a single Russian word would require a spin through the magnetic tape, on average covering half its length. It was clearly a better idea to spin through the tape only once for each whole sentence. This required you to sort the words in the sentence into alphabetical order before you start the tape spinning. I was thinking about this in my little room in Moscow State University, and I tried to write down my thoughts in Mercury Autocode, which I had learnt the previous year at Oxford while I was studying statistics. My first idea I rejected as too slow. It was rapidly followed by my second idea, which later when I got back to England, I wrote up as my second ever published scientific article. Since then, it has become famous under the title “Quicksort”. I believe it is still widely used for sorting.

Well, maybe that’s enough going backwards. I told you it was a long story. How about a little bit of going forwards? At the SIMA exhibition in Moscow, I spent the maximum possible time on the stand at which Elliotts was exhibiting an 803 computer. I met the Managing Director of the Elliott Computing Division, Eddie Nash. He was a very dynamic chap and he suggested two things : one was that I should go to work for him when I came back to England. I don’t know why he thought I would be suitable as an employee. My only qualifications were Russian and Latin and Greek. His second suggestion was that I should travel back in the empty van that had brought the computer to Moscow, and he would give me a lift for free. I could help negotiate in Russian with the hotels and restaurants and deal with the border formalities. And that was very nice because the British Council were happy to reimburse me with the sea fare that they would have had to pay for me to go back to England; that was another forty pounds. I would be rich! So I helped the driver Taffy Griffiths and Arthur Kennedy (production manager of the Computing Division) to take the van back to Britain.

When we had driven some 30 miles out of Moscow, the van suddenly began to slow down, and drew to an unscheduled stop. It had ceased responding to pressure on the accelerator pedal. On inspection it appeared that part of the linkage of the pedal with the carburettor had fallen off. We spent some time looking on the road behind, but in the end, we had to improvise a linkage from a bracket taken from elsewhere off the body of the vehicle. Unfortunately, it turned out that the logic of the linkage had flipped. In order to get the engine to accelerate, you had to release pressure on the pedal; and in order to stop it, you had to press down. After an hour’s driving, the tension in the ankle became intolerable, and short driving shifts were essential. I was spared, because I was not a driver in those days.

But it was possible to acclimatise to the reversal of control, and the main sufferers were pedestrians who made the attempt to step out into the road in front of the van, and were shocked by the roar with which our engine responded, when the driver’s foot moved to the brake pedal. When we reached the coast, we had no difficulty in persuading the ferry officials that we ourselves should drive the van onto the ferry, rather than handing it over, according to the rules, to the ferry drivers to park. On all subsequent trips to Moscow, the Elliott van would carry a full set of spares.

When I arrived back in England I went for an interview at the National Physical Laboratory to find out more about the job that they had offered me. I was a bit disillusioned by what I discovered about the rather primitive delay line architecture of their Pilot Ace computer. But in my studies in Moscow, I had also become disillusioned about the general prospects for machine translation of languages. The problem that worried me was the development and evolution of the dictionary, which would need to contain a very large number of very rare words and an even larger number of rare phrases. The problem would be exacerbated by the rapid evolution of specialist vocabularies of the various branches of Science, where every important discovery generates a whole new vocabulary of concepts and properties.

I got even more disillusioned when I talked with the Personnel Department of the Laboratory -- Human Resources, as they would be called nowadays. They informed me that since I didn’t have a science degree I could never be a member of the permanent scientific Civil Service. However, they were willing to employ me as a temporary Civil Servant at the eminent rank of a Technical Officer, which was two or three grades lower than a Senior Scientific Officer; and I could never expect to be promoted. Apparently the Director of the Computing Division of the Laboratory was quite surprised when I declined his diminished offer. I was not surprised five years later when the translation project was closed down in failure.

Of course, I had no hesitation in accepting an offer of employment as programmer from Eddie Nash. He paid me the standard graduate programmer’s salary of those days - eight hundred pounds a year - to which he added an extra hundred pounds a year because of my knowledge of Russian. It was enough to marry on in those days, I’m glad to say. On three subsequent summers (1961, 1962 or 63, and 1964), I was sent with the latest version of the Elliott computers in a van to an exhibition in Moscow, with Taffy Griffiths as driver. On getting there, my job was to exhibit the computer and answer questions from the Russian public, and talk to important people, and eventually to sell the computer at the usual 14% discount to whoever might have been chosen by the Soviet authorities to buy it. The purchasers were from what the Russians called the ‘unnamed institutes’, because they were so secret that they had no name on their front doors.

They were among our best customers. They never complained. In fact, they were so secretive that they never even wrote to us, or told us their address. But in the following years, they watched for whenever we were coming to Moscow for an exhibition, and they would send a small group of experts to talk to our technical people - because in those days every computer needed technical maintenance staff to look after it, if you remember. And at the exhibition stand they described their problems. For example, a particular power transistor kept blowing, or their paper tape punches kept getting blunt. That was easy, the transistor had been replaced by one with a higher rating, and if you want to keep your paper tape punches sharp you should use oiled tape. “Oh ! Where do you get that ? We can’t get that over here.” “Well just write to us and we’ll send you a supply.” Finally they admitted “We can’t write to you. Anyway, you couldn’t send it back.” The only solution was to bring the necessary supplies to the next exhibition, and hand them over in person!

This piece is becoming rather like Lawrence Sterne’s novel Tristram Shandy, a book of 500 pages, published in eight volumes. And towards the middle of volume four Tristram writes : “I have got no further than to my first day’s life”. So far, I’ve dealt with my conception, perhaps even my gestation, and now it is time to proceed to the birth of my computing career in 1960, when I actually started working for Elliotts. I was put under the tutelage of Pat Shackleton, who gave me a little programming puzzle - I’ve forgotten what it was. After a while I came and showed him a solution, a program in Elliott machine code. He looked through it and said “I had no idea you were as good as this! Here’s another problem for you. Write a sorting program, based on a new fast method of sorting which has just recently been invented by Shell.’ It was later called ‘Shellsort’. The method was rather complicated in concept and intricate in detail. In fact, at the time there was no way of calculating how fast it would be.

It was quite a challenging programming job, given all sorts of boundary cases. I really enjoyed the effort of optimising the inner loops. As my new colleague Cedric Dennis said, programming is like solving crossword puzzles, and being paid for it! When I showed the code to Pat, he was again quite appreciative, and the program was published in the 803 library. Rather timidly I said “I think I know a faster way of sorting”, and Pat said “I bet you sixpence you don’t”. So I described to him the method of Quicksort; he thought about it, and after a while he actually programmed it himself for the old 405 computer. It compared favourably with Pat’s own previous sorting program for that machine, because it made more efficient use of the main store held on a drum. I’m not quite sure whether he actually gave me my sixpence or not.

A wonderful bonus of our employment at Elliotts was the friendship that was forged among the programmers and with other staff. Paul King, Bob Brazier, Sheila Quinn, Roger Cook, David Smart and Cedric Dennis were among those who used to meet socially and convivially to play the game of Diplomacy in the (late) evenings. Many of us and our wives still meet occasionally for lunch.

After the sorting routine, my next job was writing magnetic tape device routines for Elliotts’ 35mm magnetic tape drives (the same width as film-stock for the neighbouring Elstree Studios). I thought I knew all about computer tapes, because while I was still an undergraduate reading philosophy at Oxford in the 1950’s, my tutor John Lucas set me the task of reading a famous paper in Mind by Alan Turing on the undecidability problem. His answer was based on the design of a hypothetical computer now known as the Turing Machine. Turing Machines have tapes, so I thought I already knew the relevant theory for computer tapes. But when I looked at the physical characteristics of the tapes that Elliotts were making at that time, I decided that perhaps the gap between theory and practice was too wide for me to bridge. So I wrote the tape routines simply to give random access for reading or writing to the individual words on the tape. A simple idea but very slow to run. To economise on space occupied by the code, my program was terribly complicated, and I suspect that nobody ever understood it afterwards. You could look up my code and its user instructions in the old 803 Library; I have seen it in the old loose-leaf binders that we used to publish our programs in. There was a copy that I saw in the National Museum of Computing at Bletchley Park.

My next task, with all of nine months experience of writing machine code programs, was to design a new programming language. I must have been an expert at that, with all my knowledge of Latin and Greek, don’t you think? Fortunately, in the library of the Computing Division at Borehamwood, I found a copy of a slim 25-page duplicated A5 booklet called “Report on the International Algorithmic Language - Algol 60” written (nominally just edited) by Peter Naur. I looked through that. There were a lot of novel ideas, which I followed with great interest. But some of the features of the language seemed a little bit complicated for our customers and salesmen to understand. Actually, I can now confess, I didn’t quite understand them myself.

So I thought I would design something a little simpler than Algol, and produced a series of draft designs, which were rapidly and happily consigned to oblivion. In the spring of 1961, there was announced a week-long school in Brighton on Algol 60, with teachers Peter Landin, Peter Naur and Edsger Dijkstra. A group of students from Elliotts registered for it, including Paul King, Jill Pym (as she then was), Roger Cook and me.

On the first afternoon of the course, instead of doing the set exercise on the course, I thought it would be interesting if I could program Quicksort in Algol 60. I would try to exploit a surprising feature of its procedures. As it said in the Report, “any other mention of the procedure name, within the procedure body, is a call to the procedure itself”. That is how the Algol 60 report explained recursion. And somehow or other I must have understood it, because I used this recursion very effectively to program my Quicksort method. I had earlier given up my attempt to program it in Mercury Autocode, because the administration of the tasks was too complicated. In Algol 60 all the administration was done behind the scenes by a stack that implemented the recursion. Rather timidly, I went up to the front of the class to show the result of my little exercise to Peter Landin. He looked at it, hmmmm, with increasing wonderment and puzzlement, and finally said : “Peter, come over here! Look at this!” So Peter Naur looked at it, and was appreciative; and that was an encouragement to write up the work for publication in 1962 in the Computer Journal, as my third scientific publication. It made an excellent foundation for my subsequent academic career.

The most important result of our attendance at the School was that coming back home in the car, with Roger Cook driving, we were discussing what we had just learned, and somebody said: “Why don’t we give up our new language and just do Algol 60?” And everybody in the car agreed that would be a good idea. “Can you do it, Tony?” was the next question. I undertook to see if I could work out a way of implementing the language on our 803 architecture. In those days we used to read respectable scientific journals in order to discover how to do things. There was an issue of the Communications of the A.C.M. in January 1961, with a famous picture of the tower of Babel on the front. It was devoted to problems arising in the implementation of Algol 60. It included articles by Cheatham, Perlis, Floyd, Barton and Irons, and an article by Peter Ingerman on thunks. The last of these described what became the standard method of implementing name parameters of procedures in Algol.

On the basis of these articles, I attempted to design the implementation of a cut-down version of Algol 60. It could not be quite the full language, for one good reason. The standard method of implementing the stack for recursion in Algol was to use index registers (B-lines) to point to the workspace of each procedure call. Most of the machines for which Algol 60 was invented and implemented had the option of address modification (indexing) every instruction. The 803 did not. To invoke address modification took two instructions, which would have doubled the length of every program, and halved its speed.

So we used the alternative technique of holding procedure workspace in fixed locations of the computer store, and ‘pushing down’ their content onto a stack whenever we detected that a procedure was being called recursively. And this meant that we couldn’t do procedure parameters. Fortunately, the technique of thunks could be used by programmers to achieve much of the same effect as procedure parameters.

There were lots of other features in the language that I didn’t know how to implement and therefore left out of my original plans. Gradually, over the months that followed, I thought of ways of implementing nearly all of them, so in the end we had a fairly full language implemented.

I was put in charge of the implementation team. The other constant members of the team were Jeff Hillmore and Jill Hoare (as she soon became). I wrote the very first module of the compiler, the lexical analysis routine, and a bit of the run time routines. I also designed the recursive structure of the whole translator, and described it in a sort of ALGOL-like notation. The rest of the team did all the real work. After a while I sort of realised that they were nearly finished. (Remember, in those days we didn’t have deadlines or timescales. We just did what we wanted, and every now and then we produced something useful).

So I wrote a note to the Manager of the Computing Division, saying that I thought that in three to six months time our implementation would be ready for distribution to our customers. At that time, there was concern over imminent loss of a sale. The customer was thinking of cancelling the sale and buying some IBM computer instead. But when the customer heard about this new Algol compiler, he was so impressed that he confirmed the sale, and shortly afterwards we actually delivered the computer. And the Algol compiler continued as a basis of the commercial success of the 803, especially in the academic market. Of course, at Elliotts our team were the heroes of the moment.

Now - Tony Hoare at the Science Museum 2008

I wondered whether this what Eddie Nash meant when he told me, early on in my career at Elliotts, “I think the best thing I ever did for Elliotts was to recruit you.” Of course, I couldn’t believe that; but if I had saved a sale worth £25,000, perhaps it was true. In the end, over 200 803’s were sold worldwide, a large total for those days, and one factor in the success was the Algol compiler.

I’m afraid that what I did next was not so advantageous to Elliotts. I designed and attempted to manage the implementation of the Elliott 503 Mark 2 Programming system. Its failure marked the end of the commercial life of the 503. So the balance of benefit to Elliotts may not be quite as favourable as Eddie expected. But I have no doubt that joining Elliotts was the best thing that I could have done for myself, preparing me well for my subsequent career as an academic computer scientist.

Editor’s note: This is an edited transcript of part of a talk given by the author at the Science Museum on 15 May 2008. Professor Sir Tony Hoare is Emeritus Professor of Computer Science at Oxford University and is now a principal researcher at Microsoft Research in Cambridge. He can be contacted at .

Obituary: Harold Hankins

I regret to have to report the death of Harold Hankins. Not, perhaps a particularly well known figure in the history of computing, but nonetheless a significant one. Harold was the driving force behind the development of a very early visual display system developed by MetroVick/AEI in 1961. Harold described the AEI 1200 computer display system and its development in Resurrection 44 and this must stand as his memorial for our purposes.

But Professor Hankins was much more than a brilliant electronics engineer. After 13 years with AEI, he returned to academic life at the University of Manchester Institute of Science and Technology (UMIST) rising to become Acting Principal (later Vice Chancellor) in 1982. Accepting this challenge at a particularly low point in UMIST’s history, he rescued UMIST from the slough of despond into which it had sunk. He was particularly well-regarded for his caring and supportive attitude towards the university staff.

Had I known that I was dealing with such a distinguished and senior academic figure in editing Harold’s note, I might have been intimidated, but he was charm itself in our discussions.

All the heavyweight papers carried an obituary, but that in The Independent (2 July) is particularly comprehensive and can be recommended to interested readers.

CCS Web Site Information

The Society has its own Web site, which is now located at www.computerconservationsociety.org. It contains news items, details of forthcoming events, and also electronic copies of all past issues of Resurrection, in both HTML and PDF formats, which can be downloaded for printing. We also have an FTP site at ftp.cs.man.ac.uk/pub/CCS-Archive, where there is other material for downloading including simulators for historic machines. Please note that the latter URL is case-sensitive.

Forthcoming Events

London Seminar Programme

London meetings take place in the Director’s Suite of the Science Museum, starting at 14:30. The Director’s Suite entrance is in Exhibition Road, next to the exit from the tunnel from South Kensington Station, on the left as you come up the steps. Queries about London meetings should be addressed to Roger Johnson at , or by post to Roger at Birkbeck College, Malet Street, London WC1E 7HX.

Manchester Seminar Programme

North West Group meetings take place in the Conference Room at the Manchester Museum of Science and Industry, usually starting at 17:30; tea is served from 17:00. Queries about Manchester meetings should go to William Gunn at .

Details are subject to change. Members wishing to attend any meeting are advised to check the events page on the Society website at www.computerconservationsociety.org for final details which will be published in advance of each event. Details will also be published on the BCS website (in the BCS events calendar) and in the Events Diary columns of Computing and Computer Weekly.

Museums

MOSI : most Tuesdays at 12:00 and 14:00. Demonstrations of the replica Small-Scale Experimental Machine at the Museum of Science and Industry in Manchester. Until around Mid November see News section.

Bletchley Park : daily. Guided tours and exhibitions, price £10.00, or £8.00 for concessions (children under 12, free). Exhibition of wartime code-breaking equipment and procedures, including the replica Bombe and replica Colossus, plus tours of the wartime buildings. Go to www.bletchleypark.org.uk to check details of times and special events.

The National Museum of Computing : Thursday and Saturdays from 13:00. Entry to the Museum is included in the admission price for Bletchley Park. The Museum covers the development of computing from the wartime Colossus computer to the present day and from ICL mainframes to hand-held computers. See www.tnmoc.org for more details.

Science Museum :. Pegasus “in steam” days have been suspended for the time being. Please refer to the society website for updates.

Committee of the Society

[The printed version carries contact details of committee members]

Chairman  Dr David Hartley FBCS CEng
Vice-Chairman  Tony Sale Hon FBCS
Secretary, Chairman DEC Working Party  Kevin Murrell
Treasurer  Dan Hayton
Science Museum representative Dr Tilly Blyth
MOSI representative Catherine Rushmore
TNA representative  David Glover
Bletchley Park volunteers representative  Pete Chilvers
Chairman, Elliott 803 Working Party  John Sinclair
Chairman, Elliott 401 Working Party  Chris Burton CEng FIEE FBCS
Chairman, Pegasus Working Party  Len Hewitt MBCS
Chairman, Bombe Rebuild Project  John Harper Hon FBCS CEng MIEE
Chairman, Software Conservation Working Party  Dr Dave Holdsworth CEng Hon FBCS
Chairman, 1301 Working Party  Rod Brown
Chairman, Harwell Dekatron Computer Working Party  Tony Frazer
Digital Archivist & Chairman, Our Computer Heritage Working Party   Professor Simon Lavington FBCS FIEE CEng
Editor, Resurrection  Dik Leatherdale MBCS
Web Site Editor Alan Thomson
Archivist  Hamish Carmichael FBCS
Meetings Secretary  Dr Roger Johnson FBCS
Chairman, North West Group  Tom Hinchliffe
Dr David Anderson
Professor Martin Campbell-Kelly
Peter Holland
Dr Doron Swade CEng FBCS MBE

Point of Contact

Readers who have general queries to put to the Society should address them to the Secretary: contact details are given elsewhere. Members who move house should notify Kevin Murrell of their new address to ensure that they continue to receive copies of Resurrection. Those who are also members of the BCS should note that the CCS membership is different from the BCS list and is therefore maintained separately.

Aims and objectives

The Computer Conservation Society (CCS) is a co-operative venture between the British Computer Society, the Science Museum of London and the Museum of Science and Industry in Manchester.

The CCS was constituted in September 1989 as a Specialist Group of the British Computer Society (BCS). It thus is covered by the Royal Charter and charitable status of the BCS.

The aims of the CCS are to

• Promote the conservation of historic computers and to identify existing computers which may need to be archived in the future
• Develop awareness of the importance of historic computers
• Encourage research on historic computers and their impact on society

Membership is open to anyone interested in computer conservation and the history of computing.

The CCS is funded and supported by voluntary subscriptions from members, a grant from the BCS, fees from corporate membership, donations, and by the free use of Science Museum facilities. Some charges may be made for publications and attendance at seminars and conferences.

There are a number of active Working Parties on specific computer restorations and early computer technologies and software. Younger people are especially encouraged to take part in order to achieve skills transfer.