Electron Oscillations without Tuned Circuits

In some earlier investigations on electron oscillations of the Barkhausen-Kurz type it was found by the author that oscillations could be produced in a positive grid valve with the usual grid-plate Lecher wire system omitted. The experimental fact that oscillations may be produced without this external Lecher wire circuit has been noted by many investigators, but few have studied the peculiarities of this particular case. The present paper describes some of the characteristics of this type of oscillator.