It is the 1970s, established typewriter brands of course had to venture out into the exciting new world of the electronic calculator. This pleasing calculator was made in 1972 for the Litton Imperial Typewriter Company under it's Royal brand as the Royal Digital 5-M.
The calculator had five functions, the four basic arithmetic functions and percentages thanks to algebraic logic, and also had memory. The calculator had an 8 digit green vacuum fluorescent tube display.
My Busicom 1210PD is a fine desktop calculator with a working printer... well it made a noise anyway but because the ribbon was completely spent i couldn't be sure on that score. I have fitted a new ribbon to the calculator, a pretty simple operation to be honest and can happily report that the printer works very well. Black and red ink is available, and it also prints lozenges!
The latest calculator to join the collection is this jolly piece of beige and black. A Lloytron Accumatic 320 to be exact and it seems to work well with it's VFD display. The calculator is pretty feature rich with a few extra mathematical functions such as square roots to go along with the basic four arithmetric functions.
This is a typical mid-1970s calculator, and can be compared to the Commodore 776M also in the collection. The 887D is a very similar calculator in many ways though noticably wider.
That extra girth allowed for an eight digit red LED display. The calculator was powered by a Commodore GRBP-89 CPU. As well as the four standard operations and percentage the calculator also had an Exchange key (EX) which reversed an operation. My 887D still has it's box, though fairly worn. The box has kept the calculator in good condition though.
This is a mid-1970s calculator which looks very similar to Rockwell's offerings of the period such as the 24RD-II. Well that shouldn't really be a surprise, if you turn it over you will see a Rockwell sticker on the back!
The calculator is a bit battered but works perfectly well. It has the four arithmetric functions and percentages, though lacks memory. Numbers are displayed on a vacuum fluorescent display.
It is 1976 and you are an executive in a top international business, but you need one of those new fangled pocket calculation machines. Well Accuron have the machine for you, it's even called the Executive! It has the four basic mathematical functions plus percentages (important for executives no doubt) and a memory. Numbers are displayed using LEDs. Unfortunately my Accuron Executive does not seem to work anymore though i'm not an executive anyway so no harm done!
As well as the typewriter, some calculators also have keys which have some sort of esoteric mysterious function which we will examine in this new series. Lets start with the lozenge! Not all calculators have this key, those that do in my collection are some of the larger mains powered printer calculators which are designed for heavy duty number crunching.
So, what does this key mean? Quite simply the lozenge means subtotal, important when you are doing the wages on a Friday morning for example. A couple of examples from our collection:
On the Silver-Reed 1250PD at least, a lozenge is generated on the print out when you press the lozenge key. Unfortunately i can't tell if this is also done on the other printer calculators i have yet as they all need new ribbons!
The Casio J-1 was a nice chunky handheld calculator from about 1978. The calculator had the basic four arithmetic functions as well as square roots, percentages, negative numbers and a memory. The cancel buttons are a rather nice orange while the others are white, black and beige. A very late 1970s colour scheme and quite frankly wonderful.
The J-1 had a NEC D1877C processor and an eight digit VFD display. Our one seems to work pretty well.
I'm on a bit of a roll with printer equipped calculators at the moment (no pun intended). The latest is this Ibico 1212 which looks like it might be an early 1990s machine, so not as old as some in the collection though does have a rather tasty VFD display. It powers up though seems to have some bit rot so can't do anything with number entered. The printer makes a sound but as there is no paper roll yet i can't tell you if that works or not!
LCD display calculators from the 1980s and 1990s are not as interesting as the LCD and VFD display machines of the previous decade but i like this simple little Radio Shack machine. It reminds me of the vogue in my latter school days for machines with solar panels, it seemed like we were entering the future with free power! The EC-458 is dual power so has a battery as well, and still works fine.
It has the basic arithmetic functions plus square root and memory. A basic machine, with a solar panel!
A typical calculator from Japan in the mid-1970s. The CX-8131 offered the basic arithmetric functions plus square roots and percentages. Plus there was a key to switch the sign of a number and memory. All results were displayed on a nice green Vacuum Fluorescent Display (VFD) display.
The calculator works pretty well, maybe not very exciting but the red, white and blue colour scheme for the keys is pleasing.
This recent addition to the calculator collection was manufactured in about 1976 and has a very pleasing 1970s beige and brown look. The calculator supports the four arithmetic functions only though displays numbers with a lovely red LED display.
The calculator does turn on though is pretty flakey. The slightest movement can clear the display. Like many calculators of this vintage the logic of the CPU seems to have suffered bit rot. It can display entered numbers but not really do anything with them.
Time to look at one of the new calculators which joined the collection at Christmas. The Busicom 1210PD is a decent sized desktop mains powered machine with a built in printer. This calculator, like the mighty Silver-Reed 1250PD, is intended for heavy duty number work such as working out the wages for the workers on a Friday.
The calculator works well, though requires a new ribbon. Despite it's age it seems to work electronically pretty well with few glitches. Numbers are shown in a nice cyan blue VFD display.
Busicom is a very important company in the history of computing. In the late 1960s Busicom wanted to build an electronic calculator. To reduce costs, they wanted to integrate the various (indeed many) chips needed into a few integrated circuits. They approached a new company in the US to design and manufacture this calculator chip, that company was Intel and the chip was the Intel 4004. The calculator which used it, the Busicom 141-PF, went on sale in 1971.
To reduce the prices charged to them from Intel, Busicom gave up their exclusivity for the 4004. Intel later in 1971 went onto sell the microprocessor, the first one to go on general sale, and they have done pretty well ever since. Busicom did not do so well, however. They went bust in 1974 and were bought out by Broughtons of Bristol who continued using the Busicom name. The 1210PD is one of these machines, it is unlikely to have a 4004 in it though maybe i shall open it up one day and check!
Merry Christmas to all visitors! This year i got two more vintage calculators for my collection rather than the typewriter fest last year (but it's been a while - at least a couple of months - since i got a new typewriter so i must fix that in early 2024!) The new calculators are a really neat looking National Semiconductor 750 Novus and a Busicom 1210PD.
Now the latter brand, Busicom, is notable. In one of their earlier machines they asked Intel for a chip for the mathematical calculations. The chip Intel produced was the 4004 which can be argued to be the forerunner of the CPUs used in PCs through to this very day...
Both machines work, the 750 Novus has some pleasing red LED numbers. The Busicom printer works though it needs a new ribbon, a project for 2024 if i can source a new ribbon.
The 796M was one of Commodore's low cost calculators which were very common in the second half of the 1970s. The 796M was made in 1976 and is very similar to the 776M which we have already covered here. The principal difference is that the 796M is black not beige!
Apart from that there isn't much difference. The 796M has the same basic four arithmetic functions, plus percentages and memory. Whatever numbers you handle on it will be displayed in a red LED display. Unfortunately, despite the calculator turning on (when fitted with a battery) it can display numbers but cannot manipulate them due to some digital decay in the CPU i assume.
There are two Boots branded typewriters in the collection, so why not a Boots calculator as well? The Boots 224 Memory is a nice late 1970s machine with a square root and percentage functions to go along with the basic four arithmetric functions. As the name implies, the calculator has memory too and works fine, numbers displayed using an eight digit VFD display. This is in fact a rebranded Casio Memory B-1.
Recently my Mum bought a new calculator with a printer built-in (a Casio HR-8RCE to be exact). I thought it would be interesting to compare it with my Silver-Reed 1250PD which i restored back to full printing order earlier in the year.
Obviously, the first thing to notice is the size difference. While the Casio is a neat little battery powered machine not much bigger than a printer-less calculator, the Silver-Reed is a mains powered behemoth. The keypad of the Casio doesn't have much give compared to the Silver-Reed, i think the latter would be a more comfortable machine to use all day.
The Casio has an LCD display while the Silver-Reed has green glowing VFD (so you can do your accounts in the dark, unless there is a power cut of course). Although the Casio's printer is adequate, the small size does mean the digits are a little thin. The print quality of the Silver-Reed is a little better, and it has red ink for negative figures.
Both are fine machines though which do their jobs well. But i am sure you all know which one i prefer.
This delightful looking calculator is one of the machines which was added to the collection last month. The Samsung Secal 800N is a mid-1970s model, probably built around 1975 or 1976. The calculator has a dedicated calculation chip. it supports the four main arithmetric functions plus percentages and square roots. It also supports negative numbers.
Despite looking in good nick, the calculator did not turn on when batteries were fitted. This is a shame as i'm sure the Vacuum Fluorescent Display would have looked superb.
I have bought quite a few calculators lately but when i saw this Commodore 798D on eBay i knew i had space for one more. It has a lovely green LED display which makes it stands out from my other working Commodores with their red LEDs. The calculator, built in 1976, is like new and seems to work perfectly.
My birthday is upcoming and i decided to spend my birthday money the best way possible, on retro office equipment! Two typewriters are pending, hopefully arriving in the next couple of days, but yesterday i received a job lot of sixteen old calculators! Some are a little more modern (though still firmly from the 1980s) than i prefer as i generally go for pre-LCD display machines but there are some interesting machines here (and only one real duplicate) which will be further explored in the months to come.
