SQB—74型声波全波测井仪测量面板的深度记号线路部分,因放大线路不够稳定,不能正常记录深度记号。我们认为,这是由于四级分立元件组成的交流放大器,元件过多及线路布置、走向等因素的影响而产生寄生振荡所造成的。我们采用低漂移、高增益的固体组件,设计了一套单独的放大与显示系统,使SQB—74型声波全波测井仪的深度记号线路满足了实际需要。下面是我们设计的深度记号系统电原理电路图。 SQB-74 full-wave sonic logging instrument panel depth mark line part, due to enlarge the line is not stable enough, can not properly record the depth mark. In our opinion, this is caused by the parasitic oscillation due to the influence of such factors as the AC amplifier composed of four discrete components, excessive components, line layout and direction. Using a low-drift, high-gain solid component, we designed a separate amplification and display system to meet the actual needs of the depth markings of the SQB-74 sonic wave logging tool. The following is a schematic diagram of the electrical circuit of the depth marker system we designed.