This circuit is from old American documentation, using a regulator integrated circuit that is uncommon today. The diodes can be 1N4002 and the transformer has a 500mA secondary.
This oscillator can generate signals from 100 kHz to more than 50 MHz depending on the crystal used...
Found in a 1980s American documentation, this circuit appears with variations elsewhere in this...
This circuit was obtained in a 1969 documentation. The circuit modulates both the emitter current and...