A signal generator circuit in which the inductor of the resonant circuit is tapped by the cathode of the oscillator tube or the emitter of the transistor.
a thermionic oscillator comprising a triode with an oscillatory circuit connected between anode and grid, and inductive coupling between the anode and grid circuits, via a tapping on the inductive element of the tuned circuit
An oscillator that uses a pair of tapped inductors and a parallel capacitor in its feedback network to produce the 180° phase shift required for oscillations.
The Hartley oscillator is an LC electronic oscillator that derives its feedback from a tapped coil in parallel with a capacitor (the tank circuit). Although there is no requirement for there to be mutual coupling between the two coil segments, the circuit is usually implemented as such. A Hartley oscillator is essentially any configuration that uses a pair of series-connected coils and a single capacitor (see Colpitts oscillator for the equivalent oscillator using two capacitors and one coil).