This small source for low consumption projects was found in an old national documentation. The transistor is for general use and the transformer has 50 to 100 mA of secondary current.
In this circuit the capacitor under test is charged at switch position A and then discharged...
This is a common circuit in the 1990s, when experimental FM transmitters were in vogue. The...
Using a piezoelectric sensor of the time, this circuit was found in the February 1994 issue of...