This circuit is from old documentation, but it can be implemented with modern transistors such as 2N2222 for bipolar and BF124 for FET. The crystal determines the operating frequency.
Found in a 90s American documentation, this circuit is used in vehicles with contact breaker. The...
We found this circuit in a 1957 Raytheon transistor publication. The circuit can be assembled with...
This TTL circuit is from a Radio Electronics magazine from February 1973. The circuit must be...