一、引言在科学研究中经常遇到大动态范围幅值的测量问题。这些测量值常采用对数定标记录,即在这些测量中要采用大动态范围的对数检波器。如果采用交流对数放大器和检波器组成对数式检波器,一般很难达到三个数量级的动态范围,且精度较低。如果采用检波后加直流对数放人器,也很难达到三个数量级,因为线性检波器的动态范围仅三个数量级。为了扩大动态范围,我们采用程控交流放大器+线性检波器+直流对数放大器+相加器组成大动态范围对数检波器,其 I. INTRODUCTION The measurement of large dynamic range magnitudes is often encountered in scientific research. These measurements are often logarithmic calibration records, that is, in these measurements to use a large dynamic range of the logarithmic detector. If the AC logarithmic amplifier and detector composition logarithmic detector, it is generally difficult to achieve three orders of magnitude dynamic range, and the accuracy is low. It is also very difficult to reach three orders of magnitude if a DC detector is used after the detection, because the dynamic range of the linear detector is only three orders of magnitude. In order to expand the dynamic range, we use program-controlled AC amplifier + linear detector + DC logarithmic amplifier + adder composed of a large dynamic range logarithmic detector, its