Oscilloscopes, Microphones, and Noise - ECE Topics #5

How to use a high-resolution (12 bit) oscilloscope to look at microphone signals directly - without preamps / etc. In this video, we look in detail at the noise that typically makes direct measurement of microphone-level signals (e.g. 3 mV) impossible. The noise is traced to radio frequency interference (RFI) from switch mode power supplies (SMPS) and strong radio signals in the area. We show how to easily fix the problem.