The date repeater
A long-standing Patek Philippe customer who in a discussion with the manufacture’s president Thierry Stern mentioned the possibility of a date strike inspired the idea behind this patented global debut.
Now, with the Grandmaster Chime, it becomes sonorous reality when the date repeater is triggered with a pusher. It sounds ten-day intervals with a double high-low strike and the remaining days with a high strike: the 23rd of a month is indicated with a ding-dong ding-dong followed by ding-ding-ding. The strikework mechanism obtains the date information from the perpetual calendar to which one side of the double-face watch is dedicated, and which controls the date displays on both sides of the timepiece.
Instantaneous perpetual calendar
The dial of the calendar face is eminently legible. It features four sub dials with analog displays grouped around the gold-framed four-digit year display in the middle.
The month is indicated at 3 o’clock, the date and leap-year cycle at 6 o’clock and the day of the week at 9 o’clock.
The time of day appears at 12 o’clock on the 24-hour and 60-minute sub dial. With the exception of the four-digit year, the calendar displays advance instantaneously and at the same time.
As regards the date, this is indispensable because the date repeater must obtain precise information, especially during the minutes before and after midnight.
The perpetual instantaneous date is also displayed on the other face of the watch where it frames the moon-phase display at 6 o’clock. A patent granted for the four-digit year display acknowledges the elegant mechanical solution which allows the year to be conveniently incremented forward or backward with two pushers.
Local time and second zone-time
When the crown of the watch points to the right, the owner sees the dial that apart from local time also indicates the time in a second time zone together with a useful day/night indication.
The same dial features the power-reserve indicators for the movement and strikework barrels, the position of the winding crown (winding, alarm setting, hand-setting), the selection of the strikework mode (Grande Sonnerie, Petite Sonnerie, or Silence) as well as a bell-shaped aperture for the alarm ON/OFF display and a small round window for the strikework isolator (disabled/enabled) display.
>>> Continue reading my deep insight into the Patek Philippe Grandmaster Chime Ref. 5175 on page 4 >>>