In this chapter, we built a simple EMF bug detector that a secret agent can use to see whether there are any bugs present in a room, such as an audio recorder or a spy camera.

There are, of course, several ways to improve this project. You can, for example, connect a battery to the project and integrate it in a small case in order to build a simple and portable EMF bug detector.

In the next chapter, we are going to build another useful device for a secret agent. We will see how to use a fingerprint scanner to secure access to important information.