LC meter. By Designing Hardware.
20:00 video:
https://www.youtube.com/watch?v=KhJiE4gL5T4
14:01 video:
https://www.youtube.com/watch?v=jytJJjer8_M
12:46 video:
https://www.youtube.com/watch?v=IciMz_u0cxw
14:34 video:
https://www.youtube.com/watch?v=zSumycEuVHI&t=4s