This circuit with three transistors was suggested in a Radio Electronics magazine from February 1963. The transistors are types of the time. Power comes from a 12 V battery.
This circuit was obtained in an Electronics Now from the 90s. The circuit uses operational...
This circuit operates at a frequency around 1 MHz, having been found in a technical documentation from...
The TAA131 used in this circuit is not very easy to find today, but an equivalent low power audio...