γ放免计数器故障诊断仪的研制

DEVELOPMENTOFFAILURE┐DETECTINGDEVICEFORγRADIOIMMUNOASSAYCOUNTER

针对放射免疫检测中必用的γ放免计数器，研制了一种采用单片机技术的γ放免计数器故障诊断仪。它能够模仿γ光子的电脉冲，产生幅度、频率可设置的脉冲信号，用于检测γ放免计数器测量部分是否正常；可检测输入信号，通过比较放大器输入输出端信号的一致性及幅度变化判断被测放大器的工作状态；采用差动放大线路，测量γ放免计数器的高压稳定性精度可达到０．１％；脉宽展宽电路使中速Ａ／Ｄ转换器能够检测脉宽为微秒级的低频脉冲信号。它专门用于γ计数器的检查、维护和故障诊断。

failures-detectingdevicebasedonsinglechipmicrocomputertechniquefordetectingoffailuresofγradioimmunoassaycounterisdeveloped.Thedevicecanoutputsignalsofvari-ableamplitudeandfrequencysimilartothepulseofγparticleforshootingproblempartsofγcounter,sdetectingsystem.Byautomaticalycomparingtheshapesandamplitudesofthetwosignalstoandfromanamplifierunit,thedevicecandistinguishiftheamplifierunitworksnormaly.Thediferential-inputamplifiercircuitgives0.1%accuracyforthemea-surementofthestabilityofhighvoltage.ThepulsewidencircuitofthisdevicealowsformiddlespeedA/Ddetectingofperiodicallow-frequencypulsewavesofmicro-secondwidth.Thisdeviceisusedspecificalyforthemaintainingandfailure-detectingofγradioim-munoassaycounter.