We found these circuits in a Popular Electronics from the 90s. The circuit has a simple low power version and a higher power version with MOSFET (VMOS) of the time.
This symmetrical source was obtained from Popular Electronics from February 1979. Transistor Q1...
This bistable and monostable Vox circuit was found in a 2002 documentation. The 556 is a double 555...
We found this circuit in a 1994 Linear Applications Handbook by National Semiconductor. The LM10...