This adjustable circuit from 0 to 200 nA was found in a 90's EDN. The components can still be found relatively easily, as they are CMOS.
This small power amplifier makes use of an output transformer given its design time. In fact, the...
This circuit is from a 1993 Italian magazine, but it can be easily assembled today. For 110 V,...
This two-way switch or control shows how to control a lamp from two points. This version is from a...