This circuit can be used as an answering password system in a store, office, or other location. The circuit is from Intersil using components of the time. The circuit is from the 80's.
This excellent circuit came out in a Japanese publication from 1971. It uses Japanese transistors of the...
This circuit is from the owner's manual of the integrated circuits used. The manual is old, which...
We found this circuit in an English documentation from 1995. The Hall sensor used is from the time...