An on-line computer assisted mass spectrometer

An analog data acquisition system incorporating an Interdata Model 4 digital computer has been designed and built for a mass spectrometer. This system has been conceived with the primary objectives of improving analytical precision and production. Automated mass spectrometer operation allows for the collection of larger quantities of data while decreasing operator involvement and consequently diminishing operator bias and fatigue. The analog signal from the mass spectrometer measuring system is digitized using a digital voltmeter and transmitted, via an interface, to the processor where the digital information is manipulated in accordance with a computer program. An additional facility is provided whereby digital data from the processor can be displayed, if desired, on a 5 decade numerical readout situated at the mass spectrometer console. Hardware is also available in the interface to provide control of the magnetic field scan rate. A function control switch at the mass spectrometer console allows the operator to convey a variety of predetermined instructions to the computer at any time during the course of a run. Thus, the system provides for on-line (real time) data processing of mass spectra as well as limited computer control over the mass spectrometer. This thesis is primarily concerned with the design and construction of the logic hardware for this system together with a demonstration of its operating ability.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat