【摘要】 为了更好地满足高频和深层勘探的采集要求．文章从地震仪的前置放大器低截止滤波器的原型设计入手，对滤波电路实施改造。即在原设计网络的基础上确定合适的电阻和电容值．增加一电阻提升网络和一补偿电路便可实现。同时，在电路中还设计了低截频切换电路，以满足不同施工区对前置放大器低截频的要求。更多还原

【Abstract】 To meet the needs for acquisition in high frequeney and deep zone exploration, the filtering circuit is improved on the basis of the prototype design of low cut filter in preamplifier. It can be achieved by determining the applicable value of resistance and capacitance, increasing a resistance lifxing network and a compensating circuit on prototype design network. In addition, a low cut frequency switchover circuit is designed to meet the requirements of low cut frequeney of the preamplifier in various working regions.更多还原