Mahjongg

I am MCJ de Jong, an electronic engineer, (of Dutch descend) specialized in designing PCB's for Analog, Digital and to a lesser degree RF systems. I am fond of retro computing, and own a collection of retro computers, and literature about retro computing.

my first computer was a nameless home-brew system based on a 6502, I designed in 1978 but it never got finished because I bought a KIM-1 and later a LMW-80.

after my study, I started working for a small hobby computer company, that among many other things sold Apple ]['s, ABC80's and Olivetti M80 systems, but also many kits. Like the Junior Computer (a KIM-1 clone), the Acorn Atom and also ZX80 kits. Many of them I assembled for customers who wanted them assembled. For owners of ZX80's I would buit in ZX81 ROM's. I also built 48K RAM and our own Floppy disc controller and Centronics printer interface into TRS-80 model I base systems, which was much cheaper than buying an expansion interface. Later I designed and sold my own Z80 computer, the Aster CT80, a much improved Tandy TRS-80 model 1 clone that also ran CP/M perfectly, and could be used as a Videotex terminal. Through the years, I designed MSX hardware, modems and audio recorders, to name just a few things, lately I am learning to layout Integrated Circuits, and am building space related hardware.