The general reaction X+Y→P+Q, catalyzed by a metal M via M+X⇄MX and MX+Y→M+P+Q (or, in another subcase, MX+Y⇄MXY→M+P+Q) renders a chemical oscillator, if in an open system X and Y are supplied from appropriate sources by influxes j1 and j2, respectively, if X shows substrate inhibition by subtracting active catalyst by forming an inert complex MX2, and if at least X is limited by an additional first order side reaction. Introduction of dimensionless variables and parameters and assumption of a partial steady state for the catalyst compounds, the sum of wbich is constant, leads to 5 (or 6) parameters, 3 of which can be easily adjusted in a wide range. It is shown that for any given values of the 2 (or 3) fixed parameters the adjustable ones can in principle be chosen in such a way that the conditions for oscillation are met. This type of oscillator is thus a parametrically universal one. By appropriate choice of the adjustable parameters the yield of products can be conducted in bursts instead of a continuous flow. Another possibility is an excitable system that fires only on triggering. Proposals toward chemical realization are discussed especially with respect to transition metal complexes.