I needed a way to heat 8 shelves in a new snake rack, so I came up with 8 individual pulse proportional thermostats on one board. The outputs would be fed to a SSR board that I had from a previous project, but any of the commercial 8 way SSR boards could be used.

Having proved the hardware on the breadboard I set about writing a small application in liberty basic to program the settings. Once everything was working fine I designed the PCB in DipTrace. The gerbers were then uploaded to PCBWay and a week later my boards arrived. Pleased to say that the installation went well and the rack is being maintained at the set temperatures required.

If anyone is interested in building this project please e-mail me for the HEX code and windows based PC application. malcolm.crabbe@micro-heli.co.uk