Video 1. Testing and Circuit for a Condenser microphone by RSD Academy (2018) Source.
Not very numerical, but shows a simple working breadboard circuit and an oscilloscope. He whistles with his mouth to get a pretty pure frequency.
That type of microphone requires a bias voltage. The circuit is in Ciro's ASCII art circuit diagram notation:
DC_9---R_10k--+--MICROPHONE--+--G
              |              |
              +-------V------+
Video 2. Soundwaves on an oscilloscope by Animated Science (2015) Source. Dude speaking to microphone. Some analysis of how different sounds look like. No circuit diagram.