This circuit triggers a small water pump when the humidity detected by the sensor is reduced in a flower bed or potted plant. The circuit must use a source according to the driven water pump.
This circuit was found in a 90s EDN. Its purpose is to increase the efficiency of operational...
This LED indicator circuit uses an LM339 comparator. The circuit was found in the January 1995...
This circuit was found in an 80's General Electric documentation. The circuit uses uncommon...