在大地测量、航海和航空上,都需要收听和应用每天在固定时间里从播时台发出来的时间信号。近二三年来中国科学院徐家汇观象台努力研究和改进了授时工作,目前该台授时工作的质量已提高到基本上可以满足大地测量等方面的要求。为了了解使用时号的单位对这方面的需要,改进今后的工作,中国科学院于4 In geodesy, maritime and aviation, there is a need to listen to and apply the time signals sent from the broadcast timepieces every day for a fixed period of time. In the past two or three years, the observatory of Xujiahui, Chinese Academy of Sciences, has worked hard to study and improve the time-keeping work. At present, the quality of the time-trial work of the station has been raised to basically meet the requirements of geodetic surveying and other aspects. In order to understand the need for the use of SIS units in this regard and to improve future work, CAS 4