I am sure there is a far better way to do any project. My stepdaughter is a senior Product Manager and my stepson is a Chartered Engineer and he frequently works as a Project Manager. They would know how to manage this project. Luckily they are too successful and busy to ever read this, thank goodness!


I tried doing the project management on a PC but gave up, and instead used 3 coloured pens, A4 paper and self adhesive address labels to cover up my mistakes. I simply found it easier. The only problem I discovered is that the paper gets a bit thick after several layers of amendments.


The project seemed to consist of many parts, all of which needed to function for the project to work. The main thing I discovered was that the first time I tried almost anything I failed, but the annoying experience enabled future success.


I had no idea how to start the project, but I found that by stabbing at various bits of the idea, I eventually was able to define what I wanted to do, and then I could look at all the parts of the problem and try and find solutions to each. Electron tube computers in the 1950s seemed to require a big team of engineers and take an eternity to build, so I looked to see if any modern design ideas could help.


The main solutions I found were, firstly to use double triode tubes to halve the physical size and secondly, to use printed circuit boards to speed construction and reduce the inevitable build errors.


I had an interesting year designing and building the Ena.Computer.


I kept trying different designs but failing to remember to keep it simple, eventually I made a design just using NOR gates. I designed a tube NOR gate and I was able to test the design on a modern simulator, which just about worked, and so I built a test rig with 5 NOR gates, and that just about worked. So I hoped that if I made the whole thing that way, the whole thing might just about work.


I also found it best not to use a separate room to build the computer, but to spread it all over the house, one bit in each room if I could. But recently I was surprised that the transfer of the Ena.Computer from the Dining room table, chairs and surrounding floor space on to the wall, was met with such joy.



Most important of all is to have a lovely wife, who knows you're daft as a brush, and that life together is brilliant.


CPU Web Ring

The home brew CPU Web Ring is an excellent place to find links to many amazing computers. There are  great personal sites with real information from a fantastic crowd of builders.

PCB Software

The Radio Spares DesignSpark PCB software is excellent. It is free, with plenty of  good help and advice online.