Relating to the construction of SDX Plus, in no particular order...
Geoff Boyd, for designing the Memotech hardware, and making it available to me.
Brian Pritchard, author of the MTX Series Operators Manual. This is really quite a comprehensive technical document, especially towards the end. Not only does it reproduce tech sheets from the chip vendors, it also includes the full MTX circuit diagrams. Invaluable when implementing hardware.
The author of the FDX User Manual and Peter Ketzschmar for making a scan of it available from his website. See the MEMOTECH MTX Computersystem website. Also for the idea of using a GAL in place of the PROM.
William Brendling for supplying PDF scans of the SDX ROM listing.
Lez Anderson for sending electronics stuff (tools and components), some of which I was able to use on this project.
And me of course, for designing SDX Plus, using the information above.