This debouncer circuit uses a transistor to produce a single pulse when the switch is triggered. The transistor conducts when the switch is opened. We found this configuration in an 80's publication.
This tachometer from a 1994 publication has a bargraph scale with the well-known LM3914 integrated...
This traditional sensor configuration with LDR was found in a 2001 documentation. The integrated circuit...
The L7805 is the SGS equivalent of the 7805. The circuit is from the SGS linear integrated circuit...