For the more convenient handling of data from an AEI MS2H mass spectrometer, it has been modified to accommodate the standard spotlight galvanometer recorder as well as the Brüel & Kjaer level recorder. This high-speed pen recorder responds logarithmically to input signals, the dynamic range of which is determined by the interchangeable range potentiometer being used. The results are now immediately available and, in consequence of the logarithmic registration, peak-height ratios can be quickly determined with a logarithmically calibrated rule.