This circuit was obtained from an American 1980s documentation. The frequency depends on the crystal and the circuit may be a PNP that reaches the generated frequency.
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...