Found in an Electronics Now from the 90s, this circuit appears elsewhere in this section and website. The diodes are for general use and the basic frequency is given by C.
Using the 2N2646 this circuit was found in a Radio Electronics magazine from July 1968. The...
The purpose of this circuit found in a 1990s Popular Electronics is to increase the current...
Found a documentation for PC from 1992, this circuit is indicated for the English power grid of...