This circuit was obtained in an American documentation from the 80's. The transistors can be equivalent to those indicated and the crystal can reach a few tens of megahertz.
This circuit is found in a 2005 Linear Technology application manual. The circuit monitors the High...
This circuit is from a 1992 Electronics Handbook. The circuit generates a special tone effect for...
We found this circuit in an old American documentation. The circuit can be applied to modern...