Multichannel analyzers are necessary tools in activation analysis. The reliability of the analytical results depends on the correction for dead time. When measuring long-lived radionuclides, this correction is automatically applied in all modern instruments by lengthening the counting time. This procedure is not sufficient in the case of short-lived species. A residual error will remain. The correction to be applied depends on the total dead time at the beginning of the measurement and on the ratio preset time/half-life. The first quantity can be read from the analyzer.