So I got myself a HiLetgo USB Logic Analyzer Device With EMI Ferrite Ring USB Cable 24MHz 8CH 24MHz 8 Channel UART IIC SPI Debug because for USD$12 + shipping how could I not? It came with a video from Amazon about how it works.
So I got myself this new bit of kit: M328 Diode Triode Capacitor Resistor Transistor ESR Meter Multi-Function Tester. When I opened the box there was no manual. But it turns out a manual is not required! This thing is so easy to use. Just wire up any old component and the device will tell you what it is!