I'm making no headway, so I decide to do a web search for an 'emulator' of a real calculator. I used to have an HP 16C when I worked for Hewlett Packard in the '90s, but I had to give it back when I left. I wonder if somebody's written a model for it? Or maybe some other interesting vintage calculator? I surf and find various HP emulators of amazing sophistication; graphing calculators, photo-realistic, an HP 16C. Some are windows applications, some are JavaScript or Java applets for on-line accessibility. I find Neil Fraser's HP 35 emulator on www.hpmuseum.org, written in JavaScript. It's becoming clear to me that there's a whole community of calculator collectors out there, and a vast array of internet resources documenting this huge subject and its history. This is fascinating, so I surf some more (I'll get back to my design in a minute) and look for vintage calculators.
I come across Nigel Tout's "Vintage Calculator Web Museum". I am immediately struck by some key phrases I haven't heard for over twenty five years: "Bell Punch", "Sumlock", "Anita". Wow, my Dad used to work for a company called Sumlock Anita in the 60s and 70s at a factory in Portsmouth that made calculators. Wasn't it part of Bell Punch?
There is a link to a sister site dedicated to the history of Bell Punch and the Anita calculators, the world's first electronic desk calculator, which I now go to with some excitement. There I find images of calculators that I'd seen being made, handheld calculators that I used to own and vast array of information that I'd all but forgotten about, and much more I didn't even know. I start to recall going to the factory as a boy...
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Me, waiting for the Christmas show, 1968. |
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David Southwell |
The factory is some way down the road (it seems to me), passing other industrial looking buildings, but we reach the entrance after a while. It is brick, but with a thirties feel to it. It is a facade to a more warehouse like factory. We enter, and have to cross the factory to reach my dad's office. He is the test manager at the factory so has his own office. The factory is in half light, as no-one is working there on a Saturday. I can still make out assembly lines. Rows of work stations for assembly or test. There is a distinct smell (I can still recall it). Very hard to describe---but technical. A mixture of solder flux, cleaning agents and other chemicals. There are completed units in some places whilst elsewhere there are exposed innards. I can see printed circuit boards and also some 'tubes'. It is a pretty open space with the rafters exposed and the strip lighting hanging down.
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Site of Rodney Road factory in summer 2004 |
We reach the office area and pass through a door. The door, and the office partition is a rather dull cream colour. The glass in the door has a sort of frosting. It is a series of vertical raised rounded ridges and I run my hand over them as we pass through. My dad's office is tidy, with an old wooden desk, looking more 50s than 70s. On it is a grey phone, with a bell and a dial. There is a pen holder; a receptical on a wooden block with a ball-and-socket hinge and a black plastic pen which tapers to a point at the top. An any-year calander is also there, with 7 day-of-the-week cards, 31 number cards and 12 month cards and I play with the cards for a while. I guess one is assumed to know the year. My dad grabs something from his office---there's not much interesting for a young boy in the office. We're off to the lab.
The lab is just along the office corridor. It is a bigger room, but not very large, and is a brighter place than the factory since it has a window. It has work benches with calculators on them. The calculators have their covers off and some with their boards out. Here I can get a much closer look at them. There are larger calculators [perhaps older models still hanging around] and smaller desktop models with angular design and, my dad tells me, Integrated Circuits. The bigger units have circuit boards with hundreds of components. It looks impossibly complicated. The smaller units still have many components, but look more managable. The back of the printed circuit boards are sharp, but have curvy lines covered in a smooth silvery metal. The top of the boards have components of various shapes with many different colours; black, silver metal cans, small cylinders with coloured stripes---a hidden code I would learn about later on in my education.
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'Nixie' tubes |
What is common to both, and what I want to see, are the displays. They are vacuum tubes. With the covers off in the strong daylight I can see the individual numbers shaped out of wires inside each tube, as well as a kind of grid. I want to see them glow. There is a unit without a cover that is set up for powering on, so my dad switches on the supply---I'm warned not to put my fingers near it. The tubes light up and a random set of numbers appear. The glow isn't as red as when the lid is on---there's a red filter on the display casing. I can see the end tubes from the side and it is more apparent how the numbers are lined up, one behind the other, in the tube.
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An Anita 1021 |
I'm allowed to play with a calculator that is fully assembled---I'm less likely to kill myself. I don't know how to operate it. It doesn't work like the arithmetic I do at school. There is no equals. So I get bored---the insides are more interesting. I definitely want to do electronics when I get older, like my dad.
A young Arabian looking engineer turns up to do some work. He works with the machines and knows how they work---this is impressive to me. He asks me about school, and do I play any sport. Soccer. He lights up when I also say cricket. Am I a batsman or a bowler? I say I prefer bowling, but the truth is I can hardly move in the batsman leg pads. Am I a spin or pace bowler? I say I'm medium pace bowler, but I doubt my arms can really throw a ball at any real pace. Perhaps I'd like to help him with his work. Yes of course! I am shown how to make paper copies of circuit drawings.
The drawings are on translucent flexible plastic sheets. They have been drawn with a dark pencil on a draughting board. The circuit drawing looks like a stylised map---almost like a map of the London underground---with lines meeting at boxes or circles with strange symbols. To make a copy I get paper sheet the same size as the drawing and sandwich them together. I then feed it through a machine with a bright glowing light discernable in its innards. Out the other end come the sheets. The paper has a faint image of the drawing. It also stinks. Fantastically the image starts to darken and in a short while a clearly legible copy is apparent. I do a set of these before it is time to go home.
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An Anita 1000 LSI |
When I get home I tell my mum what we've been doing. She asks did I know that she worked at the factory before I was born? No I didn't. She'd joined the Royal Navy as a young woman, leaving her quiet village on the Yorkshire moors, so she could do electrical work. She became a Petty Officer 'radio mechanic' in the Fleet Air Arm. It was the only way a woman could do such a thing in the 50's. After twelve years she left the Navy, but stayed in Portsmouth and got a job at the factory to carry on in the engineering field. At that time the 'girls' on the test line went through a standard procedure for test, and if the unit failed an engineer was called. My mum tells me that she didn't think she'd stay long if that was all she had to do. However, she says, dad introduced opportunities for technical training to the test girls, so that they could diagnose and fix failures for themselves. Mum tells me the way to get on is by marrying the boss, as she had then done! (though I doubt this option would be open to me). She also tells me that after they were married, dad sold this training opportunity to the girls as 'if my wife can do it, so can you!'. I ask my mum why she left---because I had you lot, which is more than enough work!
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Well wishes and Telegrams from Bell Punch Personnel (click on images to enlarge) |
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An Anita 811 |
When the handheld calculators started to be manufactured, my dad would bring home models for us to use at school. We were amongst the first kids to have them at school---they were quite expensive. So at least we were saved (or perhaps denied) from learning to use a slide rule! I had an Anita 811 for a long time. When Sumlock became Rockwell, the Rockwell models were brought home. No more sophisticated, but a sleak design and the space age Rockwell logo on the case. I also had a Unicom calculator at one point [I still have the case, but the calculator disappeared many years ago]. Rockwell had bought the American company, and I guess examples of their products were sent over to the UK. I used to see the Anita calculator boxes on the shelves at the shops in the city. I'd tell my friends that my dad made these, but they didn't seem interested. All seemed fine for a few years.
It was only as 1976 approached that it appeared that the days were numbered, and by the summer of that year all operations in the UK ceased---it seemed that quick. My dad found alternative work in procurement at Marconi, and then the names Sumlock and Rockwell became distant memories, and almost forgotten.
I have now started to collect Anita calculators that were made at the Portsmouth factory. The handhelds like the Anita 810 and a desktop Anita 1000 LSI are part of my small collection, but also Rockwell calculators, like the 8R, that were made in Portsmouth before manufacture was moved to Mexico. Some of these items are quite rare (and hence expensive) and it occured to me to simulate an Anita calculator so that I could use it as my desktop calculator at work and that others, without access to such things, could experience what these devices were like to use (and the operation of the early units are quirky to say the least). I looked back at Neil Fraser's HP 35 simulator written in JavaScript, and thought I could do something like this with a bit of research and if I had an image of an Anita calculator.
And here the collecting community came to the rescue. I did not have an Anita 811, but found an image on the web at Voidware. I asked Hugh if I could use his image, and not only did he say yes, but supplied all the examples from the manual that he'd typed in for me, debugged and corrected code and a host of other assistances. I found other variants of the Anita 811, made for the Triumph-Adler company in Germany, and Tony Thimet supplied an image of a Triumph 81. Since first releasing the Anita 810/811 model, I have some really good, positive feedback, and the interest is strong. Writing this article has been prompted by encouragement to do so by Gerard Evrard in France and James Redin in the U.S. So now, having acquired a unit, I'm working on a model for the Anita 1000 LSI desktop, and try and capture an earlier age when the glowing tubes first captivated me. This will be available soon, and I have an offer of an Anita 1011 LSI image to simulate this as well. In the long term I hope to simulate a selection of calculators from the Portsmouth factory to give a sort of dynamic museum charting the evolution of these devices to complement the wealth of information already out there. This may take some time, searching for images and operational information (especially manuals). I'm trying to make these models as accurate as possible so that one gets a 'feel' for using them, as well as operational accuracy. Even if just a few individuals learn something about the company and its products then it seems worthwhile. In any event, I now have an Anita 810 on my computer desktop---better get on with that memory interface then.
Simon Southwell
17th February 2004