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 circuit presented may use any general purpose transistor. The indicator is an LED and...
This source was found in a 1982 American publication, but can be easily assembled using 2N2995 (PNP...
Found in a 1980s documentation, this circuit uses as base a component of the era. The formula for...