| 摘要 |
PROBLEM TO BE SOLVED: To eliminate demanding endurance for long time to an operator and the like on upper system and prevent lowering of work efficiency by making immediately obtainable of a frequency standard of higher accuracy after power making or when needed. SOLUTION: To a GAS signal receiver 2, given is a function outputting information of deviation against the true frequency of frequency of clock signal CK as a frequency deviation signal FDD of higher accuracy than 1 second pulse PPSa. Provided is a frequency difference detector 7 detecting frequency difference between the frequency of a frequency standard output signal FST and the frequency of the clock signal CK corrected with frequency deviation signal FDD. A control voltage generator 4 is made a circuit specifying and selecting at least one of the time difference detection signal TDD and a frequency difference detection signal FDD and outputting a control voltage CV of the level corresponding to these signals. |
