This circuit is from General Electric documentation from 1970. The transistors can be of general-purpose types, except for the power that can be a BD136.
This configuration, different from Motorola's 1990 Linear Databook, uses a voltage reference...
This ultra-low consumption circuit was originally designed to be powered by a solar panel or small...
This double-T sine wave oscillator was found in the December 1995 issue of Electronics Now...