Found in a 1964 publication, this circuit makes use of transistors from the time. It operates on frequencies up to 3 kHz.
This circuit was obtained in a 1991 Electronics Handbook. The publication no longer exists, but...
This circuit makes use of an uncommon integrated circuit. It can provide a power of 6 W when...
This circuit of the 1970s uses Germanium transistors. Changes can be made to use silicon...