Thesis (Diploma (Electrical Engineering))--Cape Technikon, 1983. / The Coastal Engineering and Hydraulics Division of the National Research Institute for Oceanology (NRIO) undertakes research projects so as to be able to supply specialised expertise and consultancy services in coastal engineering with special reference to the needs in South Africa. Physical models of harbours, beaches, etc. are built at NRIO and are used mainly for sediment and breakwater studies. To collect the vast amount of data in the tests done on these models a Model Hall Data Acquisition System, MHDAS, was developed (Holroyd, 1980) to provide a data-logging facility and also to provide the control signals required to co-ordinate model operation and thus permit automatic model testing.