关于DL—1型无输入变压器数字电平表输入电路的研制

Balanced Input Circuit of Level-Meter Without Balanced Input Transformer on Model DL-1 Digital Level-Meter

本文以DL-1型数字电平表为例,讨论了如何去掉电平表中输入变压器而用电子有源器件代替的问题。作者以5G28运算放大器组成平衡式放大,在DL-1型电平表中使用获得了成功。

This article mainly discusses how to use operational amplifier for designing a new electric circuit which can be used as an input circuit of level-meter without input balance-Transformer.As an example,mode 1 DL-1 digital level-meter gives the full design steps.