This circuit was found in an Electronics Now from the 90's. The integrated regulator circuit and the power transistor must be equipped with heat radiators.
For analog lines, this circuit was found in the August 1994 issue of Electronics Now magazine. The...
This circuit has a traditional configuration often found on this site. The transistor must be...
This 4-digit counter, using CMOS technology, was found in a 1997 documentation. The circuit is...