Indicated by Popular Electronics, in an edition of the 90's, this circuit seems doubtful because of the inductance used, which must be large.
This circuit uses a capacitor to store energy. The capacitor is charged by closing S1 by a moment. Them,...
This circuit is both a signal injector and a signal follower. A key selects the operating mode. The...
The difference between this circuit and the previous one is that it uses PNP transistors. The...