This circuit is from old documentation, but it can be implemented with modern transistors such as 2N2222 for bipolar and BF124 for FET. The crystal determines the operating frequency.
The TPA3100D2 integrated circuit from Texas Instruments (www.ti.com) consists of an efficient...
This circuit was found in a 1965 General Electric publication. The circuit can be adapted to...
This circuit, which combines a bipolar with any JFET, was found in the April 1993 issue of...