This circuit is from an article about operations in a Radio Electronics magazine from around 1968. The transistors are types of the time and the power is not the greatest.
The amplifier shown in figure 2 is based on the MAX9715 integrated circuit from Maxim...
This stage for JFETs was found in a 1965 US publication, but is valid for modern components. |...
This circuit was found in a Japanese publication from 1971. The circuit uses components from the...