Calculators Sold by Sumlock And Made By Other Companies
Nixdorf Visible Record Computer
Nixdorf Visible Record Computer
Ian Partridge, was a training instructor for Sumlock service engineers from 1968 until 1975 first at Clerkenwell Road, London, then later at Apsley, near Hemel Hempstead when the training centre moved. Ian kindly provides the following information about the Nixdorf accounting machines that were sold by Sumlock-Anita:
The Nixdorf Visible Record Computer appears to be a development of the same company's Logatronic programmable mini-computer for invoicing.
The machine was built into an office-desk sized arrangement. There was a specially modified IBM 'golf ball' typewriter set into the desk-top as an output device and a numeric keypad to its right hand side. Fitted to the typewriter was a feed unit for feeding in and printing the ledger account cards. Later versions of this had a reader for cards which carried a magnetic strip for user information. These were a source of trouble, I remember, aligning and setting these mag-stripe readers up to read correctly could be quite a job!
The electronics were housed on the left hand side in a 'filing-drawer' type of chassis, with individual plug-in circuit units. These were about 12 inches square by some one and a half inches thick - extruded aluminium frames with large printed circuit boards fitted into them. From memory there were several separate 'boards':
- CPU.
- 'micro' memory - machine coding (equivalent to ROM these days).
- 'macro memory' - application instructions (which was programmed individually for each customer).
- Read/write memory board (today's RAM).
- Input/output board - interfaces.
There was also a power supply unit, of course.
The memory units were all hard programmed by threading wires through a matrix of cores, and women were employed specially to do this 'knitting', working to programmers' charts.
I was fortunate to go on several courses both with Nixdorf in Paderborn and later
with RUF in Zurich on these systems (see the RUF Accounting Machines). Also, for information
about Heinz Nixdorf, the company, and its computers, including a photograph of one of these machines, see http://www.xnumber.com/xnumber/nixdorf2.htm.
Ian Partridge adds the following information:
My introduction to these systems was when I was asked to add them to my repertoire as a training instructor. We (ie. Sumlock) had one or two branches which looked after the
Nixdorf VRCs – in North London and at Haywards Heath, among them. Somewhere around 1970 I went on a six week course at Nixdorf's training school in Paderborn. Later, after Sumlock had taken on the RUF agency for the UK, I went
several times to RUF-Buchhaltung, as they were called, in Zurich, with side trips to Trossingen, home of Hohner, where the systems were manufactured. I also had to learn quite a bit of German - but to this day, my German is
better in connection with electronics and computing than in the everyday sense! We actually learned the functioning of the electronics, and fault-finding, right down to component level. These days, it's all done by changing
complete boards or modules - another sign of changing times!
If you have further information about the Nixdorf Visible Record Computer (especially photographs), the development of Anita calculators, or know of somebody who worked there, please get in touch with me.
