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Shortly after the launch of the Anita handheld range (1973), Sumlock Anita was bought by Rockwell International. As well as continuing with the Anita range, manufacture of Rockwell calculators was started at the Portsmouth factory, in the UK. The images below show models known to have been made in Britain.
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10R | 8R | 18R | '76 | 20R |
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21R (uk) | 21R (mex) | 30R | 31R |
The calculators have increasing feature sets from left to right. The 10R is the simplest calculator in the range, with just the four basic operations, and the '+' key doubling up as the equals. The 8R is a basic four function calculator with added percent (I don't know why the range number is less than the 10R). The 18R (and the bicentennial '76 version next to it) add a memory register with store and recall, whilst the 20R/21R (which have identical functionality) extend memory operations to add, subtract, multiply and divide. The 20R/21R also have a ninth digit for displaying 'minus', extending the range of the calculator. There are two case styles for the 21R; one from the UK factory, and the other from Mexico. The 30R and 31R add some arithmetic functions (square, square root and reciprocal, as well as register interchange functions). They are identical in function except for displaying of error conditions. Manuals for all these calculators (except the 10R) can be found on the manuals page. A 10R manual may be found here.
As well as calculators sold under the Rockwell name, versions were made which were branded for retailers and outlets. These generally had redesigned cases, but later models were the same as their Rockwell counterparts with just a change in logos and labelling. In Britain, the department store 'House of Fraser' sold a range of calculators that were made in the U.K. In the States both Sears & Roebuck and Radio Shack also had their own versions, and were generally made in Mexico. These calculators date from around 1974 to 1976.
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8F | 18F | 30F | 20R Type 2 | |
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8M | 801.58190 | EC-220 | EC-415 | 9TR |
The first three images above are House of Fraser calculators. These are Rockwell calculators in a more stylish case and with an 'F' suffix instead of an 'R'. In functionality they are the same as their Rockwell counterparts, and were made at the Portsmouth Factory.
The next image, on the right of the first row is a Rockwell 20R, but in a second type of case. Made at the Portsmouth factory, the only known example was found in France, and so maybe the style was for the continental market. This is followed on the next line by an almost identical calculator, the Sears 8M, made for Sears & Roebuck in the U.S. Notice that it has an identical case to the House of Fraser models, but with different markings. It is also a Rockwell 20R (despite its name), and is unlikely to have been made in the U.K., but certainly shares the same pedigree. Also the Rockwell 10R has had a makeover for Sears, but with, perhaps, a colour scheme more indicative of the times.
Following on is a Radio Shack EC-220 calculator. This was a Rockwell 8R branded for that company. This particular variant was never made at the Portsmouth factory, and probably all the examples were made in Mexico for the U.S. market. However, I'm including it here as it relates to the Rockwell models made in the U.K. and because I like the design of the case! The EC-415 is included for the same reason, and is a re-branded 30R.
The image on the far right is another 8R variant, the Rockwell 9TR, made for sale through the U.S. store 'True Value'. It is still clearly marked 'Rockwell' though, but is very green. This too, as far as I know, was not made in the U.K.
A pdf README file is available for the Rockwell simulators.