| 摘要 |
<p>1,030,476. Automatic frequency control. GENERAL ELECTRIC CO. Ltd. Aug. 16, 1963 [Aug. 23, 1962], No. 32520/62. Heading H3A. In an A.F.C. system for a variable frequency oscillator 1, the output of the oscillator is mixed with a selected harmonic of a first reference oscillator 6 in a mixer 7 which supplies an output which is mixed with a selected harmonic of a second reference oscillator 9 in a second mixer 11 and the output of this mixer is compared in a phase detector 13 with an oscillation generated by oscillator 4 to provide a D.C. voltage to control the oscillator 1 via reactance valve 14. The reference oscillators may operate at 1 Mc/s. and 100 kc/s. respectively and their harmonies are selected by manual controls 2 and 3 which control respectively the tuning of band-pass filters 5 and 10. Oscillator 4 is an interpolation oscillator and its frequency may be controlled by an arrangement, Fig. 3 (not shown), similar to that shown.</p> |
