For around $25, the Neoteck TS20D is a fully-featured, well-made, and decently accurate tool that will handle most multimeter-related tasks. It's small enough to drop into a pocket or toolbox, durable ...

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.

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? A digital multimeter is an indispensable tool for testing, diagnosing, and ...