The Elektor book publication with the above title describes a set of Arduino-driven test and measurement instruments — from their principles of operation right up to hands-on use, including programming and fair scrutiny of strengths and limitations. In this article, we plunge into the book at a relatively advanced point where some of the basic functions such as frequency generation and frequency measurement get software refinements aiming for precision and practical use in the home lab. If the Arduino deserves one place in your maker lab, for sure that’s inside a multifunction, all-DIY test instrument for real use on the bench!