Bob's Basic Wide Range Ring Tester

I wondered if it was possible to make a wide-range inductor "ring" tester which does most of the functions of the Blue2 Ring Tester (   • "Blue2" inductor ring tester demonstration.  ) but with common readily available components, and this is the result. It's bigger, uses a 9V alkaline battery and has no low battery warning or automatic power-down but gives basically the same measurements. All the details about how to build one is on my website at https://zilogbob.com/Basic%20Digital%...