observatory clock造句

• This was controlled by electrical pulses from the observatory clock.
• Fredrick Martin Meach of the Canadian embassy in Paris recorded the time announcements in English, which were stored on strips of photographic film and played back under control of the observatory clocks.
• A number of suggestions had been made for a centrepiece for the safety zone, including relocating the Perth Observatory clock there, or using the site for the Lord Forrest Memorial or the State War Memorial.
• A divider chain was put into service so that all of the CHU signals were derived from Western Electric standard crystal oscillators, with the seconds pulses divided down and monitored by continuous comparison with the observatory clocks.
• In former times, before the distribution of accurate time signals, it was part of the routine work at any observatory to observe the sidereal times of meridian transit of selected'clock stars'( of well-known position and movement ), and to use these to correct observatory clocks running local mean sidereal time; but nowadays local sidereal time is usually generated by computer, based on time signals.