The output pulses from scintillation detectors are amplified in conventional feedback amplifiers and transformed into a bipolar wave form, which passes the discrimination level of the following EFP 60 trigger circuit at a given time after inception of the scintillation pulse, independent of its amplitude within a wide range. If these standard pulses are shaped and fed into a fast coincidence circuit, even for NaI(Tl) resolving times of the order of 10−8sec can be obtained. The main limitation of the method is due to time jitter of the standard pulses caused by statistical fluctuations of the rising edge of the photomultiplier pulses which results in a reduction of coincidence efficiency.