Multi-range frequency generator using frequency dividing techniques

摘要

1,113,843. Automatic frequency control systems. CIT-COMPAGNIE INDUSTRIELLE DES TELECOMMUNICATIONS. 20 Jan., 1967 [25 Jan., 1966], No. 3158/67. Heading H3A. A variable frequency oscillator 10 is synchronized with a reference oscillator 16 by means of a phase discriminator 14 supplied with inputs from the two oscillators via fixed frequency dividers 11 and 15 and a variable frequency divider 12. In the circuit shown the dividers 11 and 15 are binary counters the stages of which are connected to ganged switching means C 1 and C 2 the rotors of which are connected respectively to an output terminal 18 and to the oscillator 16. The switch C 1 alters the range of the output frequency and thereby alters the steps in which the oscillator 10 is tuned; the switch C 2 alters the steps in an opposite sense, so that the oscillator 10 is tuned in equal steps in all its ranges. The output frequency within a range is determined by the setting of divider 12 which may be a pulse counter of the integrated circuit type.