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.
Mouser Electronics is now shipping DA14585, a kit for the development of voice remote control...
In its first version this article was written in Portuguese for a Brazilian magazine and...
The integrated circuits used in this oscillator are not very common today, as we obtained it in...