This circuit is from documentation from 1965 but can be easily implemented today using modern transistors. We can use BD136 for Q1 and TIP42 for Q2. The TIP must be equipped with a heat sink.
This oscillator from an old publication uses one of the first commercial transistors, the CK722....
The integrated circuit used in this configuration is not common today. The zener determines the...
With good filtration, a battery charger can be used as a power source. The filter shock can be the...