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.
This polarization step for electret microphones was found in an Electronics Now from the 90s. The...
This control for bass, midrange, and treble was found in the March 1995 issue of Electronics Now...
We found this circuit in a 1993 documentation. It is a high input resistance millivolimeter whose...