This 1970s RCA circuit can be triggered by light or dark, depending on how the LDR is connected. The controlled load depends on the triac.
The integrated circuits used in this 1999 project are not very common today. However, they can be...
This 3-digit thermometer, suggested by Texas Instruments, uses 3 integrated plus the display, with...
This circuit is from the National Semiconductor FET Databook. The coil data is provided with the...