On this Day in 1981: Launch of the Sinclair ZX81

Me! We used them in Computer Studies in school so I remember I did quite a bit of programming in Basic on it. First thing I remember programming on it was trying to create a random number generator - can't remember if I succeeded or not! I do remember destroying the keyboard quite quickly playing Daley Thompson's Decathlon...my dad quickly bought me a joystick after forking out for its repair.

I had one of the very first before they were on general release, purchased from the Timex factory shop in Dundee, where they were made. I still have it, along with the 16K RAM pack, but cannot remember what I programmed on it.

My brother worked for a time in a store which starting selling the ZX81 and brought one home to learn how to use it for demonstration purposes (though it might have been a ZX80). I had a go, having learned both Basic programming and Fortran at school (rather unusually for the seventies), but my attempts to program it were foiled by the rather meagre (1Kb) memory as I kept coming up against error messages about lack of memory. When I did finally get the program into memory, there was insufficient memory to run the damn thing.....

I don't remember what it was supposed to do, but possibly find prime numbers.

Julie,

Are you sure that it was the ZX81 you are thinking of and not the Sinclair Spectrum? The ZX81 had a near indestructible (and difficult to use) keyboard and is still the only coffee-proof computer I have ever come across.

Alasdair

Alasdair Anderson:


Are you sure that it was the ZX81 you are thinking of and not the Sinclair Spectrum? 

Ahhhh the Sinclair Spectrum....?


We had one of those after we'd grown out of the ZX81 and then the Spectrum 2 as well which, if I remember rightly, came with an integrated tape deck to load the programs. ?

I never owned ZX81 but I purchased my first PC The ZX Spectrum ( "ZX81 Colour") an 8-bit personal home computer that was released in the United Kingdom in 1982 by Sinclair .

While originally called the "ZX81 Colour" and "ZX82" during development, the system was renamed the ZX Spectrum in order to promote its colour display, which was a significant upgrade from its black and white predecessor, the ZX81. It proved immensely popular in various incarnations over the years and remains the most successful British computer ever made.

I used it to interface to a water irrigation controller that I constructed with a friend. But mostly we used it for games.    

I owned a ZX81! I've actually still got it up in the loft. The basic machine came with a whole 1K of RAM - and there was the RAM pack that took it up to a mind-boggling 16K. I also had the thermal printer, which produced its output on what resembled a silver toilet roll. I seem to recall it needed a beefed-up power supply for the printer. I also invested in a Kempston keyboard - it stuck over the ZX81's touch pad and had "clicky" keys that seemed to work intermittently. I vaguely remember the first thing I programmed was a formula that plotted a sine wave. Anything more than a few lines of Basic required the 16K Ram Pack - and does anybody else recall that you had to keep the machine completely still while typing, otherwise the TV screen would flicker and you'd lose the lot and have to start again?


And let's hear it for the ZX81's contemporaries, like the Commodore PET, VIC 20, Oric 1, BBC Micro, ZX Spectrum etc. (Cue the background music from the Hovis advert...)

Yes, my rather perceptive Aunt purchased me a ZX81 as a 12-yr old. it spawned my career.


My Aunt was from the era that had programmed "for the government" in the 40s and 50s during the early days of computing. (whatever that meant) As a woman she was prevented from continuing to make computing her career. These days programming for the government in the very early days counjours up all sorts of exciting exploits but that may just be romantic nonsense. 

In any case, my Aunt purchased me a ZX81 mostly to give me an outlet for my interest in code and electronics. Although it clearly gave her a kick to think that computers could be purchased for the home and that her young nephew was excited and interested.

I have got one of those. Built it myself as I was fascinated to see the micro electronic components inside. Still at school, much of the electronics I had exposure to still had thermionic vacuum tubes in them.  May have cleared it out of my mothers loft quite recently. It went with me to university, Big mistake as did not have much credibility with an 8 bit processor.