| 摘要 |
A wide frequency deviation voltage controlled crystal oscillator includes a multiple section bandpass filter containing a plurality of crystal or ceramic elements. One embodiment includes a plurality of crystals which are connected into parallel conduction paths. The crystals have resonant frequencies which are separated by small, selected intervals so that the oscillator may be adjusted to a wider range of frequencies than prior art oscillators. Alternatively, the same result may be achieved by using crystals with the same resonant frequency and connecting each crystal to a capacitor having a selected value. In another embodiment a multiple section crystal or ceramic bandpass filter is substituted for the parallel conduction paths. The principles of the invention are applicable to a number of different devices, including the ringing circuits used in color televisions to perpetuate the color bursts which appear in the blanking intervals of the incoming TV signals.
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