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 found this circuit in the May 1996 Electronics Now magazine. The relay must have a voltage...
The shield circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor of 1994....
Up to 0.5 A DC motors can be controlled by this circuit. Direction change is achieved by a logic...