Tag Archives: Sinclair ZX81

The Home Computer

Sinclair ZX81

Thomas John Watson, Sr. was president of International Business Machines (IBM) who was responsible for the company’s growth into an international force from 1914 to 1956.

For a man who achieved all this it is perhaps surprising that he made one of the least accurate predictions ever when he said in 1943, “I think there is a world market for maybe five computers” . Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977 must have been reminded of this when he said “There is no reason anyone would want a computer in their home.”

Well they were both wrong and in 1981 Sir Clive Sinclair launched his home computer and almost thirty years later almost every house has one. The Sinclair was small, black with only 1K of memory, and it would have needed more than fifty-thousand of them to run Word or Excel, but the Sinclair changed everything. It didn’t do colour, it didn’t do sound, it couldn’t remember anything and it didn’t even have an off switch. But it brought computers into the home, over a million of them, and created a generation of software developers.

Up until this moment I, like most people, hadn’t given a lot of thought to owning my own computer. There was a mainframe machine at work which clanked and whirred away in a mysterious sort of way in an air-conditioned room at the back of the building but I didn’t get to use it and I didn’t even have a terminal on my desk.

Cory Environmental Contract Manager

Cory Environmental Contract Manager

Anyway, when this thing arrived at W H Smiths for £69.95 (or £49.95 if you built it yourself) I was quickly convinced that it was something I really needed. I visited the store a couple of times and just touched the box and poked a finger at the demonstration machine but this was just a bit of tyre kicking of course because I had no idea why I needed it or what I was going to do with it. On the third visit I made up my mind and bought one.

It came in a pack with an instruction manual and some software, some games including space invaders and chess and some geeky stuff that I never used like ‘make a chip’. It had to be connected to a cassette recorder and the software downloaded whilst making a reassuring screeching noise to confirm that there was actually some data transfer taking place. Eventually the tape would clunk to a stop and if you were lucky the software began to work.

The Complete Spectrum

After a while magazines started to print code for new games and applications and I would spend hours typing them in via the flat plastic keyboard but just one mistake – which might have been a typing error in the magazine – and it didn’t work. Typing this code into the machine made me realise that there wasn’t much to this programming malarkey at all and I quickly learned that you didn’t need to be a computer scientist with a brain as big as Mount Everest to be able to do some BASIC programming for yourself.

I am absolutely certain that I will never ever be able to follow a knitting pattern or flat pack furniture assembly instructions but I discovered that when it came to BASIC programming I was a bit of a natural and I became consumed by the thing.

This product was so successful that just over a year later on 23rd April 1983 a new, bigger and better looking model was launched called the Sinclair Spectrum. This had 4K of RAM so now programming possibilities were almost infinite.

I would spend hours hooked up to a portable TV set creating and designing my own programmes and doing everything that I could to squeeze every last bit out of the memory.

There were two programmes that I was most proud of both of which I submitted to a magazine and had them printed. The first was a game of Connect4 played by two players or against the computer itself; I was proud of that and my friends and family were really impressed. My favourite however was a database programme for recording and storing cricket averages. Even though I say so myself this was a neat little programme that I used for a couple of years to keep the office team records.

Rugby Rural District Council Cricket Team

Rugby Rural District Council Cricket Team

We all owe so much to Sir Clive Sinclair because the introduction of his home computer was one of those moments in history when social change and human development goes through a momentary period of rapid acceleration and without the Sinclair ZX81 and the Spectrum I would not be sitting in front of my Packard Bell writing my blog!

Sinclair Spectrum

Scrap Book Project – Television Sets

When I was a boy in the 1960s television sets were rather basic and only received two channels BBC and ITV and the signal was received via a large ‘H’ shaped metal aerial, usually bolted on to the chimney.  Just turning them on was quite a long process because instead of today’s micro chips, televisions had an antiquated system of valves, wires and resisters and these took some time to ‘warm up’.  After a minute or so you would get sound and then after another minute or so (if you were lucky) a grainy black and white picture with flickering horizontal lines would slowly start to appear.  Most television sets needed about fifteen minutes to warm up, I seem to remember.

Today, modern slimline sets are useless for putting ornaments on top of, but in the 1960s they were a big piece of wooden furniture just right for picture frames, vases and holiday mementoes so it was always quite accurate to say ‘Isn’t there a lot of rubbish on the TV!’

Television sets were always breaking down as well, half way through a programme there would be a ‘PING’ and the picture would disappear into a bright white spot in the middle of the screen like a bright star falling into a black hole and that was it until the television repair man responded to request to come by and fix it by replacing the broken tube in the back, which was a bit like replacing a broken light bulb.  This wasn’t easy either because we didn’t have telephones so someone had to get on their bike and go to the television repair man’s shop to report the fault and make the request.

There was excitement on 20th April 1964 because on that day BBC2 became the third British television channel but unlike the other channels available at that time was broadcast only on the 625 line Ultra High Frequency system, so was not available to viewers with 405 line Very High Frequency sets. This created a market for dual standard receivers which could switch between the two systems and anyone who wanted to receive the new channel was obliged to go to the expense of upgrading their television sets.

Rediffusion Rugby

1960 Television Set

This sort of thing still goes on today.  Last year I was looking for a new computer and was advised that I would have to buy a PC with an updated operating system as my old Sinclair ZX81 was no longer in production.  This sounded all well and good until I was told that I would have to replace most of my software as well because it would be incompatible with the new operating system.  What a con!

On the subject of computers the computer language BASIC was also first introduced in 1964, which was a real breakthrough and led to the greater accessibility and later the introduction of home computers.

The Home Computer

Thomas John Watson, Sr. was president of International Business Machines (IBM) who was responsible for the company’s growth into an international force from 1914 to 1956.

For a man who achieved all this it is perhaps surprising that he made one of the least.accurate predictions ever when he said in 1943, “I think there is a world market for maybe five computers” .  Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977 must have been reminded of this when he said “There is no reason anyone would want a computer in their home.”

Well they were both wrong and in 1981 Sir Clive Sinclair launched his home computer and almost thirty years later almost every house has one.  The Sinclair was small, black with only 1K of memory, and it would have needed more than fifty-thousand of them to run Word or Excel, but the Sinclair changed everything.  It didn’t do colour, it didn’t do sound, it couldn’t remember anything and it didn’t even have an off switch. But it brought computers into the home, over a million of them, and created a generation of software developers.

Up until this moment I, like most people, hadn’t given a lot of thought to owning my own computer.  There was a mainframe machine at work which clanked and whirred away in a mysterious sort of way in an air-conditioned room at the back of the building but I didn’t get to use it and I didn’t even have a terminal on my desk.

Cory Environmental Contract Manager

Anyway, when this thing arrived at W H Smiths for £69.95 (or £49.95 if you built it yourself) I was quickly convinced that it was something I really needed.  I visited the store a couple of times and just touched the box and poked a finger at the demonstration machine but this was just a bit of tyre kicking of course because I had no idea why I needed it or what I was going to do with it.  On the third visit I made up my mind and bought one.

It came in a pack with an instruction manual and some software, some games including space invaders and chess and some geeky stuff that I never used like ‘make a chip’.  It had to be connected to a cassette recorder and the software downloaded whilst making a reassuring screeching noise to confirm that there was actually some data transfer taking place.  Eventually the tape would clunk to a stop and if you were lucky the software began to work.

After a while magazines started to print code for new games and applications and I would spend hours typing them in via the flat plastic keyboard but just one mistake – which might have been a typing error in the magazine – and it didn’t work.  Typing this code into the machine made me realise that there wasn’t much to this programming malarkey at all and I quickly learned that you didn’t need to be a computer scientist with a brain as big as Mount Everest to be able to do some BASIC programming for yourself.

I am absolutely certain that I will never ever be able to follow a knitting pattern or flat pack furniture assembly instructions but I discovered that when it came to BASIC programming I was a bit of a natural and I became consumed by the thing.

This product was so successful that just over a year later on 23rd April 1983 a new, bigger and better looking model was launched called the Sinclair Spectrum.  This had 4K of RAM so now programming possibilities were almost infinite.

I would spend hours hooked up to a portable TV set creating and designing my own programmes and doing everything that I could to squeeze every last bit out of the memory.

There were two programmes that I was most proud of both of which I submitted to a magazine and had them printed.  The first was a game of Connect4 played by two players or against the computer itself; I was proud of that and my friends and family were really impressed.  My favourite however was a database programme for recording and storing cricket averages.  Even though I say so myself this was a neat little programme that I used for a couple of years to keep the office team records.

Rugby Rural District Council Cricket Team

We all owe so much to Sir Clive Sinclair because the introduction of his home computer was one of those moments in history when social change and human development goes through a momentary period of rapid acceleration and without the Sinclair ZX81 and the Spectrum I would not be sitting in front of my Packard Bell writing my blog!

Television Sets and BBC2

When I was a boy in the 1960s television sets were rather basic and only received two channels BBC and ITV and the signal was received via a large ‘H’ shaped metal aerial, usually bolted on to the chimney.  Just turning them on was quite a long process because instead of today’s micro chips, televisions had an antiquated system of valves, wires and resisters and these took some time to ‘warm up’.  After a minute or so you would get sound and then after another minute or so (if you were lucky) a grainy black and white picture with flickering horizontal lines would slowly start to appear.  Most television sets needed about fifteen minutes to warm up, I seem to remember.

Today, modern slimline sets are useless for putting ornaments on top of, but in the 1960s they were a big piece of wooden furniture just right for picture frames, vases and holiday mementoes so it was always quite accurate to say ‘Isn’t there a lot of rubbish on the TV!’

Television sets were always breaking down as well, half way through a programme there would be a ‘PING’ and the picture would disappear into a bright white spot in the middle of the screen like a bright star falling into a black hole and that was it until the television repair man responded to request to come by and fix it by replacing the broken tube in the back, which was a bit like replacing a broken light bulb.  This wasn’t easy either because we didn’t have telephones so someone had to get on their bike and go to the television repair man’s shop to report the fault and make the request.

There was excitement on 20th April 1964 because on that day BBC2 became the third British television channel but unlike the other channels available at that time was broadcast only on the 625 line Ultra High Frequency system, so was not available to viewers with 405 line Very High Frequency sets. This created a market for dual standard receivers which could switch between the two systems and anyone who wanted to receive the new channel was obliged to go to the expense of upgrading their television sets.

This sort of thing still goes on today.  Last year I was looking for a new computer and was advised that I would have to buy a PC with an updated operating system as my old Sinclair ZX81 was no longer in production.  This sounded all well and good until I was told that I would have to replace most of my software as well because it would be incompatible with the new operating system.  What a con!

On the subject of computers the computer language BASIC was also first introduced in 1964, which was a real breakthrough and led to the greater accessibility and later the introduction of home computers.

A Life in a Year – 23rd April, The Age of the Home Computer

Thomas John Watson, Sr. was president of International Business Machines (IBM) who was responsible for the company’s growth into an international force from 1914 to 1956.  For a man who achieved all this it is perhaps surprising that he made one of the least ever accurate predictions when he said in 1943, “I think there is a world market for maybe five computers” and Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977 must have been reminded of this when he said “There is no reason anyone would want a computer in their home.”

Well they were both wrong and in 1981 Sir Clive Sinclair launched his home computer and almost thirty years later almost every house has one.  The Sinclair was small, black with only 1K of memory, and it would have needed more than fifty-thousand of them to run Word or Excel, but the Sinclair changed everything.  It didn’t do colour, it didn’t do sound, it couldn’t remember anything and it didn’t even have an off switch. But it brought computers into the home, over a million of them, and created a generation of software developers.

Up until this moment I, like most people, hadn’t given a lot of thought to owning my own computer.  There was a mainframe machine at work which clanked and whirred away in a mysterious sort of way in an air-conditioned room at the back of the building but I didn’t get to use it and I didn’t even have a terminal on my desk.  But when this thing arrived at W H Smiths for £69.95 (or £49.95 if you built it yourself) I was quickly convinced that it was something I really needed.  I visited the store a couple of times and just touched the box and poked a finger at the demonstration machine but this was just a bit of tyre kicking of course because I had no idea why I needed it or what I was going to do with it.  On the third visit I made up my mind and bought one.

It came in a pack with an instruction manual and some software, some games including space invaders and chess and some geeky stuff that I never used like ‘make a chip’.  It had to be connected to a cassette recorder and the software downloaded whilst making a reassuring screeching noise to confirm that there was actually some data transfer taking place.  Eventually the tape would clunk to a stop and if you were lucky the software began to work.

After a while magazines started to print code for new games and applications and I would spend hours typing them in via the flat plastic keyboard but just one mistake – which might have been a typing error in the magazine – and it didn’t work.  Typing this code into the machine made me realise that there wasn’t much to this programming malarkey at all and I quickly learned that you didn’t need to be a computer scientist with a brain as big as Mount Everest to be able to do some BASIC programming for yourself.  I am absolutely certain that I will never ever be able to follow a knitting pattern or flat pack furniture assembly instructions but I discovered that when it came to BASIC programming I was a bit of a natural and I became consumed by the thing.

This product was so successful that just over a year later on 23rd April 1983 a new, bigger and better looking model was launched called the Sinclair Spectrum.  This had 4K of RAM so now programming possibilities were almost infinite.

I would spend hours hooked up to a portable TV set creating and designing my own programmes and doing everything that I could to squeeze every last bit out of the memory.  There were two programmes that I was most proud of both of which I submitted to a magazine and had them printed.  The first was a game of Connect4 played by two players or against the computer itself; I was proud of that and my friends and family were really impressed.  My favourite however was a database programme for recording and storing cricket averages.  Even though I say so myself this was a sophisticated programme that I used for a couple of years to keep the office team records.

We all owe so much to Sir Clive Sinclair because the introduction of his home computer was one of those moments in history when social change and human development goes through a momentary period of rapid acceleration and without the Sinclair ZX81 and the Spectrum I would not be sitting in front of my Packard Bell writing my blog!

A Life in a Year – 20th April, Television Sets and BBC2

When I was a boy in the 1960s television sets were a bit basic and only received two channels BBC and ITV and the signal was received via a large ‘H’ shaped metal aerial, usually bolted on to the chimney.  Just turning them on was quite a long process because instead of today’s micro chips, televisions had an antiquated system of valves, wires and resisters and these took some time to ‘warm up’.  After a minute or so you would get sound and then after another minute or so (if you were lucky) a grainy black and white picture with flickering horizontal lines would slowly start to appear.  Most television sets needed about fifteen minutes to warm up by which time the programme was almost finished, I seem to remember.

Today, modern slimline sets are useless for putting ornaments on top of, but in the 1960s they were a big piece of wooden furniture just right for picture frames, vases and holiday mementoes so it was always quite accurate to say ‘Isn’t there a lot of rubbish on the TV!’

Television sets were always breaking down as well, half way through a programme there would be a ‘PING’ and the picture would disappear into a bright white spot in the middle of the screen like a bright star falling into a black hole and that was it until the television repair man responded to request to come by and fix it by replacing the broken tube in the back, which was a bit like replacing a broken light bulb.  This wasn’t easy either because we didn’t have telephones so someone had to get on their bike and go to the television repair man’s shop to report the fault and make the request.

There was excitement on 20th April 1964 because on that day BBC2 became the third British television channel but unlike the other channels available at that time was broadcast only on the 625 line Ultra High Frequency system, so was not available to viewers with 405 line Very High Frequency sets. This created a market for dual standard receivers which could switch between the two systems and anyone who wanted to receive the new channel was obliged to go to the expense of upgrading their television sets.

My Sister Lindsay with the TV around about 1968, I think she is on her X-Box…