2-Component Hartley Oscillator

Although Elektor never actually launched a design contest under the name “low component-count oscillators” the author was challenged by ‘Three Component Oscillator’ published in July/August 2001. The result is shown here, representing a reduction in component count of no less than 33.3%! The audio field has been left though in favour of RF.This Hartley oscillator can be built from just one FET and a coil. The coil has a tap to provide the amount of positive feedback the circuit needs to start and maintain oscillation.