It is well known (but often forgotten) that the concept of inductance, without defining a complete loop of current, is completely meaningless! Some books give inductance of a length or wire, some people talk about the inductance of a via, and still others talk about the inductance of ground braids, etc. All these discussions about inductance ignore the requirement for a complete loop before the total or loop inductance can be discussed in any meaningful way.
In this article, square unshielded wire loops are compared to shielded solutions including simple techniques to build them in your lab. Some examples are included to show that unshielded loops often work as well as shielded loops in some applications, especially for injecting signals into circuits.
This article dispels some of the misconceptions surrounding inductance and to encourage electrical engineers to think more clearly about these physics.