The integrated circuit used in this 2002 project is not very common. It is powered directly by the telephone line, requiring no power supply.
This circuit is quite old, from 1964, but can still be mounted with BC558 transistors. The circuit is...
This circuit is from a 1965 General Electric manual. It uses components from the time that admit...
This system of sequential lights for shop windows, discotheques, stores, does not use integrated...