We found this code key or coded keyboard in a publication from the 90s. The circuit uses components that are still common today and is powered by a 12 V voltage according to the relay used.
This simple circuit that senses energy cables (alternating current) through the field produced was found...
This third-order filter was found in a 1975 publication. The circuit must be powered by a...
This circuit that also has a Power On reset was obtained from a 2005 Linear Technology manual. The...