1976 年 78 巻 p. 33-52
The general consideration of "Phase-Locked Loop by use of the sampled data control" is descrived especially on the digital sampling and holding system of the phase difference between the VCO as local standard and the reference VLF wave. An investigation is made on the mathematical treatment and the numerical calculations, with respect to the responses of the theoretically derived model. According to this results, the system parameters of loop gain, time constant, sampling time, and settling time are determined. It is proved that the holding system of VCO has a good stability when reference VLF wave is off the air, and that the aging auto-compensation system operates satisfactorily against a long term frequency drift. Several recorder charts observed in practice to detect the fractional frequency errors are shown, which prove this equipment functions as expected in accordance with the design factors.