This simple logic level tester was found in Radio Electronics from the 90s. The inverters are of the 4009 type and the power comes from the circuit being analyzed.
This fuzz effect is from a 1988 Italian publication, but it can be easily assembled, as the...
The circuit presented, from 2006, serves to control loads at a distance, robots, etc. It can be...
We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the...