A multichannel crystal oscillator
Alwin Hahnel · IRE Transactions on Vehicular Communications · 1955
The oscillator type described in this paper permits the selection of an undesired one of an unbroken series of harmonically related frequencies without having the aforementioned disadvantages. It consists of two sections: A crystal oscillator operating at the fundamental to the desired output frequencies and an oscillator which is periodically phase-controlled by the fundamental oscillation such that its output frequency spectrum contains only harmonics of the crystal oscillator frequency. Frequencies that are not harmonieally reb tf.d to the crystal frequency are not generated. The oscillstor operates simultaneously in the range of the desired output frequency and at the crystal controlled fundamental to it. This simplifies the circuitry eucb that only one vacuum tube, one quartz crystal end two tuned circuits are required to produce an output spectrum of high order harmonics. The spectrum energy is concentrated about the harmonic nearest to the fre~uency of the periodically phase-controlled oscillator.