This circuit, which can be used to indicate the movement of an object, was found in NASA documentation. The circuit uses a sensor made with liquid in a container as shown in the figure.
The oscillator in figure 1 can be used in alarm, call or warning systems, producing a sound of...
This circuit was found in a 1965 General Electric manual. It is intended for cars that have...
The component used, which is not common today, is an electronic attenuator. In this application of the...