This humidity sensor indicates the different levels of conduction of the sensors through an LED bar. The circuit is from Popular Electronics and must be powered by cells or battery.
We can either supply this circuit with 12 V if we use a relay for this voltage as well as 6 V if...
Two NAND gates are used in the configuration shown here to perform as a monostable triggered by...
Frequency and active cycle of this circuit are fixed by the two crystals that may have different...