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.
This test consists of a simple Hartley oscillator using a transformer of the type found on older...
n be assembled with BC558 transistors for low power transistors and a BD136 for the output. The...
This oscillator takes advantage of the 2000 ohms headphone inductance as the oscillator circuit coil....