I have always enjoyed electronics since the age of about 8 or 9. One day I went to work with my dad, a heating and ventilation technician who was in charge of a number of heating control systems in government buildings. I was fascinated by the giant control panels, about 2m high and running a considerable length down the boiler room full of lights, switches, temperature chart recorders, timers etc. Being curious I wanted to know all about it, flick this switch and one of the boilers started a fire-up sequence – pre-heat oil, raise oil pressure, open valve, ignite. Whilst all the lights went through the different stages, in the background you could hear and see a boiler going through its paces and then at the end whroom the thing ignited. It didn’t stop there, gauges monitored pressures and temperatures and if something went wrong other lights would illuminate and an alarm would sound and dad would have to take some corrective action. For a young lad all this was absolutely brilliant, being curious I wanted to know how it all worked, I was old enough and intelligent enough to know it was not done by magic. Dad opened up the side of this huge control panel and we went in, it was a mass of wires and other unknown boxes, all neatly arranged and interconnected, wow and I still didn’t know how it worked.
The Christmas after that exposure dad made for me a very simple control panel in a wooden box, it had a couple of lights on it, switches and a bell. The lights and switches were all neatly labelled up with really exciting names just like at his work. Inside dad had wired things up to a battery so when one switch was flicked a lamp illuminated in green, another switch lit up a red ‘danger’ lamp and a press button made the bell ring. After playing with this for a awhile I opened the back and started to see how it was wired together. Once I understood this I made simple changes, swapping switches around, for my birthday I got a buzzer and wired this up so that it sounded when the danger lamp illuminated. The next Christmas I got an electric shocking coil, my first interest I suppose in medical applications of electricity and electronics, I wired this up, drilling a hole and putting in another switch then had great fun shocking my parents, other family and friends. I was definitely hooked.
When we went to the library I look and got books on simple electric circuits and made most of these things up at home following the directions and instructions given, some worked, others didn’t. At Christmas after my 10th birthday my parents I got an electronics kit, wow. This contained a number of components, most I had never heard of, resistors of different values, capacitors and two transistors. With it you could make over 20 different projects. I guess this was a fore-runner of today’s breadboards but much simpler. The base was a sheet of wood with holes drilled in matrix formation, there were a number of cards pre-printed with a circuit diagram at junctions there were holes. you laid this on the base then pressed spring terminals through the circuit holes and then between the springs you connected the components. I had great fun making up the circuits, flashing lights, a light that would come on only when it got dark, a squeaky sound generator that went to an ear-piece and others that I can’t remember. I think in the end I got all the projects to work, the spring contacts were the most problem, they did not give reliable connections and tarnished very quickly. For my 11th birthday I got a 1-transitor radio kit based on the same principle of connection. I never, ever did get that darn thing to work.
My first exposure to computing electronics was when I started at secondary school. The head of maths in his room and running almost the length of it had what I now know is a shift-register made from many transistors and little lights, all in a large glass display case with construction along similar lines, but better than the spring terminals of my home sets, this has screw-down terminals and brass strips interconnecting the stages. He would only demonstrate this to the upper school, so I had to wait a few years to see this in action, we were not allowed to touch any of it, just observed what happens. At school in the later years, I got my first introduction to binary notation, arithmetic and Boolean logic.
About the age of 12, one of my aunts knowing my interest in electronic things introduced me to her next door neighbour a man who was a radio amateur, he had down the bottom of his garden a shed full of radio receivers and transmitters plus a whole load of other kit and components. he used to communicate with others all round the world, some speaking and others by Morse code, that he clicked out and got replies. I caught the bug and started going along on Friday evenings to his club. My interest grew in this field and there were people there, like me that were fascinated with electronics and radio and we could talk the same language, or at least be on the same wavelength! They were a very friendly bunch, keen to talk and explain things, I was still very technically innocent beyond simple lamp-switch circuits and components. The years that I was there I learnt a lot and soon started going along to theoretical classes to learn more about what all these components do, how we can make them work and produce something useful, the objective being to get my own radio transmitting licence for which an exam was required to be passed covering electronic theory as well as rules/regs regarding radio communications. I passed the exam around age of 14, before I took any GCSE equivalents at school but due to age restrictions couldn’t get my licence until I was 16. I was much more interested in construction that communication aspects.
It was off to college after school. The climate was vastly different then I had a job in telecommunications, my employer sent me to college and paid me as well for this. Naturally I had to study telecommunications, which a lot any way was about electronic principles. We had a free-choice module and I chose computing. They had a ‘table-top’ HP computer – it was the size of a small fridge with rows of lamps and toggle switches to set up memory addresses and for data, all in binary. If my memory serves me well it had 256-Bytes of ferrite core storage, a far cry form today’s even modest computers, I dread to think how much that little beastie cost.
As a hobby I regularly got monthly periodicals for electronics, there were several around back then. I made a few simple circuits up out of these, money was a main limitation for a young teenager. With work and more money allowed me to be more ambitious in my electronics and I followed a whole series of articles in one mag – making your own computer. Again this was nothing fancy, it was all done in binary and was based around a 4-bit processor. With various expansions, add-ons etc over the course of about 2-3 years I must have spent nearly £1,000 on the things and you still needed to enter and read things in binary, but at least I could save my programs on to a cassette recorder.
Computers were growing up fast for the home enthusiast let alone in the business world and I progressed to a single board computer that I had to solder all the 100+ IC’s on to as well as other components. This come with a 2k ROM that contained the BASIC programming language, could display real text on a TV screen and use a keyboard. It cost about £250.
My employer sent me on a two-week course out in the country all about how to use an 8080 microprocessor to control a model train. This was absolutely brilliant, we covered how to interface switches, signals, points to a micro, write the code to make things happen in sequence and even touched on PWM speed control. A really useful course.
Professionally I went on to mange a PDP-11 min-computer, there were 24 users on the system and it had a hard drive with removable media the size of a washing machine, capacity 10Mb! I then moved on to R&D of electronic instrumentation for telecommunications, many of the devices I designed and built were based around the Z80 or 8080. At home and as a hobby, I much preferred the 6502 and used this quite a bit, later 68000 series.
I became bored with telecommunications so left and went to university and studied medical electronics, which started a whole different chapter of my electronics life – more perhaps another day.
Posted in: Uncategorized