| 摘要 |
PURPOSE:To pick up a signal with frequency 3 times of the oscillation frequency of a crystal resonator directly and effectively by adding simple parts to the circuit of a crystal resonator in a transistor oscillation circuit with a crystal resonator. CONSTITUTION:After defining the capacitor of crystal resonator as C'1, C'1, indactance L1 and capacitor C3 constitute a resonance circuit, which selects the frequency twice of the oscillation frequency fo of crystal resonator. Since the admittance observed from input point 1 to the side of crystal resonator is polarlized with the frequency of 2fo, transistor TR1 is not excited by 2fo but is excited strongly by 3fo; the signal of the excited transistor is picked up from signal output terminal 2 as output through the paralleled resonance circuit (resonating with 3fo) consisting of capacitor C4 and indactance L2. |
