This circuit is from an old Signetics documentation. It can be implemented with modern operational amplifiers. The power supply must be symmetrical.
This circuit triggers a load when the sensor detects humidity. The triggering point is adjusted by...
We found this circuit in a 1994 publication. It makes use of a divider for 16 384 CMOS type 4060. By...
This circuit triggers a remote doorbell when the phone rings. The circuit is for the 110 V mains...