前一个时期大量生产的 UJI 型电位差计,线路灵敏度较高,在工厂和实验室中广泛地把它用来测量几十毫伏以下的低电势。这时,UJI 型电位差计的补偿回路电流是2毫安,工作电流是32毫安。所以就要用蓄电池或相应的精密稳压电源,否则工作电流就不稳定,直接影响测量精度。1967年我们在一只 UJI 型电位差计上作了试验,把线路及电阻作了变动,使工作电流从32毫安降为3毫安。这样,电源只要用两节甲 The UJI type potentiometers, mass-produced in the previous period, have high line sensitivities and are widely used in factories and laboratories to measure low potentials of tens of millivolts or less. At this time, UJI-type potentiometer compensation loop current is 2 mA, the operating current is 32 mA. So we must use the battery or the corresponding precision power supply, or the working current instability, a direct impact on measurement accuracy. In 1967 we tested on a UJI type potentiometer that changed the line and the resistance so that the operating current dropped from 32 milliamperes to 3 milliamperes. In this way, as long as the power with two A