An Example of Processing of Ion Intensity Signals from Mass Filter by Analog Hybrid Computer

Abstract

An analog hybrid computer EAI 180 has been combined to a quadrupole mass filter UTI-KE 100 C to process the ion intensity signals from the mass filter in analog form without changing the signals to digital form. The combination is made only by receiving mass scanning ramp voltage and ion intensity signals from the mass filter. No other procedure is applied to the mass filter system. Mass selection can be made quite arbitrarily on a CRT screen by comparing the scanning voltage to a reference voltage during the usual high speed mass scanning display(100 msec/300 mass). The ion intensity signals are processed in the logic control and peak hold circuits, then the output signals are summed and/or divided in the analog calculation circuits to give a ratio and/or other quantities. Performance tests have proved the combination works quite well and the new system has followed in real time the quick changes of the ion intensity ratios. The system will be capable of being a new tool in the respiratory gas analysis.