GB1208306A - Improvements relating to converters for amplitude analysers or pulse height analysers - Google Patents

Abstract

1,208,306. Measuring voltages. DAIMLERBENZ A.G. and FRAUNHOFER-GESELLSCHAFT ZUR FÍRDERUNG DER ANGEWANDTEN PORSCHUNG E.V. Oct.18, 1967 [Oct. 18, 1966], No.47502/67. Heading G1U. [Also in Division H3] A signal converter for use with an amplitude analyzer or pulse height analyzer comprises two parallel circuits, each comprising a series connected capacitor and diode 2, 3 or 2a, 3a, there being a switch 8 or 8a in parallel with each diode, and a series connected threshold element 5 or 5a and mono-stable element 6 or 6a, the output of each mono-stable element controlling the switch in the other circuit to periodically close the switch and bring the junction of the associated capacitor and diode to earth potential. The output of the converter is a signal representing successive peak to peak values of an input signal, the mean values of successive peak to peak values, the time spacing of successive peak values or the time spacing of peak values which fall within a given amplitude range. In the Fig. 1 arrangement, an input signal, Fig. 2a, is fed to a pre-amplifier 1, and depending on whether the input signal is increasing or decreasing at a given time, one or other of the capacitors 2, 2a feeds a voltage through an amplifier 4 or 4a to a common addition amplifier 7 which gives the output shown in Fig. 2b, the maxima and minima of which respectively represent the minima/maxima and maxima/minima voltage differences of the input signal. In Fig.4, the outputs of amplifiers 4, 4a are inverted and halved in value in amplifier 12 and added to the input signal in amplifier 13, the composite signal being sampled at the times of the peaks in the outputs of amplifiers 4, 4a to give the arithmetic mean values of the voltage differences between successive maxima and minima in the input signal. In a modification, Fig. 6 (not shown) which is a combination of Figs. 1 and 4, only those peak values are selected from the output of amplifier 7 for which the mean values as measured by the Fig.4 circuit fall within a predetermined range. In another modification, Fig. 7 (not shown) two sawtooth generators (22, 23) controlled by the mono-stable elements 6, 6a, produce signals representing the time spacing between successive maxima and minima of the input signal. In a modification of Fig. 7, Fig. 9 (not shown), the sawtooth generators are also controlled by two Schmitt triggers (29, 29a) supplied with the input signal, so that the outputs of the generators represent the time spacing between peak values, of the input signal, which fall within a predetermined range, as set by the Schmitt triggers (29, 29a).