You can’t visualize what’s happening in a circuit any better than using an oscilloscope. Historically, the devices were expensive and bulky. I’ve had many Tektronix and HP scopes that stayed ...

Even if you do not follow [GreatScott!]´s steps to build a simple oscilloscope, don´t throw away that vintage TV!, it is a great source of analog parts. The flyback transformer can be used to ...