Over on YouTube our hacker [VIP Love Secretary] shows us how to make a simple MOSFET tester. This is a really neat, useful, elegant, and simple hack, but the video is kind of terrible. We found ...

To measure a zener diode’s breakdown voltage, you need a dc voltage source whose voltage exceeds that of the zener voltage. In Figure 1, resistor R SER provides voltage drop between V IN and V ZEN. In ...