So a few months ago, I stumbled upon a thing at Adafruit.com called a "Charger Doctor" which was really just a Multimeter designed to slip inline with your USB cable. It was $7.50 and I liked it.

While using a digital multimeter to diagnose electrical problems on customers’ equipment, I frequently hear the comment, “I’ve got one of those multimeter things, but I never learned how to use it.” ...

A friend of mine has bought a second hand vehicle with a lot of added wiring installed behind panels that are glued in, some of which are behaving mysteriously. Due to high input impedance, a ...