Telephone directory

Have you see how small the telephone directory is these days? Its more like a pamphlet than a directory! In the olden days the telephone directory was a weighty tone, so thick that it was used as one of the tasks in televised strongman competitions, to tear directories in half! Even i could tear a current one though i'd struggle with the Birmingham directory from 1980 (as below).

The directory is mostly just lists of numbers, in alphabetical order of the phone line owner. It was interesting to look through at numbers i remember from decades ago (yet i still struggle to remember my own mobile number!) In the centre of the directory is the rather fabulous Green Pages detailing the various services of the General Post Office telephone service - Post Office Telecommunications (soon to become British Telecom) which we will look at in further detail at a later time.

Mysterious keys (9) : Olympia's variation on margin-release

As we saw earlier in this series, the margin-release key allows you to override the margin stops on a line, handy if you just need one or two extra characters to finish a word. However, there is no standard way to represent this function, Olympia used four dots on the Olympia SF Deluxe which isn't very descriptive but i suppose once you know what it means...

SR10

The latest typewriter in the collection, a Silver-Reed SR10, is a rather nice one. A new ribbon has been procured so we will fit it soon.

National Semiconductor Novus 750

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.

Trimphone

Time for another addition to the collection, however it is not a typewriter or a calculator this time! Instead, i have bought a GPO Trimphone 722, the slim more modern counterpart to the venerable 746 dialphone. The trimphone is a bit battered but looks very nice, it is a shame i won't be able to make it ring out with it's warbling chirp chirp ring as i don't have a landline anymore, though my Mum does...

Update: I have tested it on Mum's landline. I even made a video which will be posted here at a later date...

Some more copying

The SR10 typewriter i received recently came with a couple of bonuses, some paper (of which more later) and some carbon copy sheets. These are better than the ones i bought in 2022, being only single sided unlike the other copy sheets so your top original sheet doesn't get ink on it on both sides. I had a play using my SR100 typewriter and, as you can see below, they work very well for when you need to keep a copy for your private archives...

Now the paper is interesting as it is a different size to the A4 and Foolscap i have used previously. The paper is 203 x 254mm or 8 x 10in, a size known as Quarto. This is a nice paper size to use, luckily a whole pack of it came with the SR10.

Busicom 1210PD

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!

Typewriter 29

And the first new typewriter to join the collection in 2024 is here! Number 29 in the collection is a rather fetching Silver-Reed SR10 in blue (the kind of machine we have a few of in various incarnations). It seems to work well enough though needs a new ribbon for sure. The typewriter came with a pile of paper and carbon copy sheets, even the manual too so that was a good buy!

Typing on an Atlas

Let's do some typing.