本文介绍探测器的构成。1)带有阻抗变换的探测头。其响应元采用悬空结构,阻抗变换探测头的场效应管是采用带有二极管的结型场效应组合管,二极管起偏置电阻作用,省去一只超高阻。阻抗变换头用金属壳密封,保护探测器的高阻抗匹配,使探测器性能的稳定性有保证。2)前置放大器。介绍电路原理图,简述其二极管在导通前,呈高阻状态,组合管的转 This article describes the structure of the detector. 1) Probe with impedance transformation. The response element adopts a floating structure. The field effect tube of the impedance conversion probe is a junction field effect diode with a diode, which acts as a bias resistor, eliminating the need for an ultrahigh resistance. Impedance conversion head sealed with a metal shell to protect the detector’s high impedance matching, so that the stability of the detector performance is guaranteed. 2) preamplifier. Introduce the circuit diagram, a brief description of the diode before the conduction, was a high resistance state, the combination of tube turn