在电子线路实验及课程设计中,一般情况下电路并不复杂,信号频率也不高,因此测试电路并不困难。但在有些情况下,由于忽略了仪器的合理接地,进行动态测试时很不稳定,致使示波器波形颤动、毫伏表指示摆动,数字频率计不能正确测频。遇到这种情况,学生往往不知所措,本文就此问题谈一点体会。 目前大多数电子仪器都要使用电源变压器,因此仪器外壳将对变压器绕组产生感应电势。给仪器接地,可使仪器外壳与大地保 In the electronic circuit experiment and course design, under normal circumstances the circuit is not complicated, the signal frequency is not high, so the test circuit is not difficult. However, in some cases, due to ignoring the instrument properly ground, the dynamic test is very unstable, resulting in oscilloscope waveform wobble, millivoltmeter indicates swing, the digital frequency meter can not correctly frequency measurement. In this case, students often overwhelmed, this article talk about this issue a little experience. At present, most of the electronic equipment to use power transformers, so the instrument shell will have induced potential transformer winding. To the instrument ground, the instrument shell and the earth can be guaranteed