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 circuit is from an Electronics Hobbyst Handbook from the 90s, being valid for panels of the...
This circuit can generate signals from 80 to 800 Hz with an amplitude of 0.3 V. We find it in a...
This circuit is from an American publication from the 60's. The power is on the order of 600 mW....