Patek Philippe Minute Repeater Alarm Reference 1938P-001

To celebrate the 85th birthday of Philippe Stern, president of the manufacture from 1993 to 2009 and current honorary president, Patek Philippe has developed Reference 1938P-001, a new chiming watch with minute repeater and alarm, chiming the programmed time on the repeater mechanism’s two gongs.

Patek Philippe Minute Repeater Alarm Reference 1938P-001
Patek Philippe Minute Repeater Alarm Reference 1938P-001

This 30-piece limited edition watch is also distinguished by its platinum Officer’s style case and its Grand Feu black enamel dial presenting a portrait of Philippe Stern in Grand Feu white and gray miniature painting on enamel.

The Patek Philippe Minute Repeater Alarm Reference 1938P-001 limited edition houses a completely new movement developed solely for this piece and never to be used again. With the reference number 1938, the watch evokes the year of the honorary president’s birth.

Patek Philippe Minute Repeater Alarm Reference 1938P-001

Minute repeater is Philippe Stern’s favourite complication. For this exclusive watch, Patek Philippe combined minute repeater with an exclusive acoustic function: an alarm chiming the programmed time.

This complex mechanism was one of the five acoustic functions and one of the two patented world firsts unveiled in 2014 for the manufacture’s 175th anniversary on the Grandmaster Chime Reference 5175, the most complicated Patek Philippe wristwatch (20 complications), equipped with the manually wound caliber 300 “GS AL 36-750 QIS FUS IRM”.

Joining the regular collection in 2016 as Reference 6300, the Patek Philippe Grandmaster Chime unites a grande sonnerie, a petite sonnerie, a minute repeater, a date repeater chiming the date on demand and an alarm chiming the programmed time.

For the new Reference 1938P-001, Patek Philippe developed the new caliber R AL 27 PS self-winding movement incorporating minute repeater and alarm mechanisms.

The challenge was to create a watch in which the minute repeater and the alarm chime on the same two classic gongs while retaining the system of a slide piece set into the left flank of the case, a prized visual signature of the Patek Philippe minute repeaters.

This required that upon actuation of the slide, the movement be capable either of instantly striking the time displayed on the dial (in minute repeater mode) or of putting the strike on hold until the time displayed corresponds to the programmed time (in alarm mode).

Contrary to classic minute repeaters, where winding by means of the slide instantly releases the striking-work, the addition of an alarm system made it necessary to be able to disengage the strike-work barrel from the strike train (the quarter rack, the minute rack, the hour beak).

All these technical constraints called for the addition of 227 parts, including a lever and column wheel for selection of the chiming mode and a fusee device with a strike-work detent mechanism that temporarily disconnects the power source (the strike-work barrel drum) from the striking mechanism–a system usually reserved for grande sonnerie watches.

In developing caliber R AL 27 PS its designers filed four new patents for mechanisms making it possible, notably, to switch with complete safety from one chiming mode to the other; to delay the alarm strike until the right moment; to ensure, in every case, the correct strike sequence of “hours, quarters and minutes”; and to guarantee that the strike-work barrel is always fully armed with each actuation of the slide –so that the watch can always, if necessary, sound up to 31 strikes for the alarm (12:58).

Furthermore, the strike-work barrel was fitted with a slip bridle to avoid any excessive tension in the spring.

The push-piece integrated into the crown serves to select the chiming mode, which is displayed in a small bell shaped aperture at 3 o’clock. When the watch is in minute-repeater mode (black bell) the user can actuate the repeater slide at any time to hear the chimes of the hours, quarters and minutes elapsed since the last quarter.

When the watch is in alarm mode (red bell) the slide must be actuated again to wind the alarm (the bell changes from red to white). When the alarm has been actuated but has not yet sounded (white bell) it is possible to return to minute repeater mode by pressing on the push-piece without this releasing the strike.

The 12-hour programmable alarm time is set from one quarter-hour to the next by means of the crown pulled out to the middle position and the Breguet-style center alarm hand in rose gold pointing to the scale in powdered rose gold on the periphery of the dial. To allow the maximum number of chimes to be heard, the alarm of Reference 1938P-001 always strikes two minutes before the programmed time.

Accordingly, if the alarm has been set for 3 o’clock, instead of three low-pitched strikes (which could easily go unnoticed) the watch will sound two low-pitched strikes, three double high-low strikes and 13 high-pitched strikes, making 21 strikes in total.

Safety systems prevent any damage in the event of incorrect manipulation –such as successive attempts to arm the slide when the alarm has already been actuated, or adjusting the movement time when the watch is striking.

Patek Philippe Minute Repeater Alarm Reference 1938P-001

The tribute to Philippe Stern continues on the 18K gold dial with its portrait in Grand Feu white and gray miniature painting on enamel, on a ground of Grand Feu black enamel.

Applied Breguet-style numerals and Breguet-style hour and minute hands, all in white gold, contrasting with the rose gold of the alarm hand and scale, lend their elegance to the time display.

Measuring 41mm in diameter, the platinum case is hand polished throughout. With its straight lugs and screwed-in strap bars, it recalls Patek Philippe Reference 3960, a limited edition timepiece launched in 1989 to the manufacture’s 150th anniversary.

Patek Philippe Minute Repeater Alarm Reference 1938P-001

Like all Patek Philippe watches in platinum, Reference 1938P-001 has a diamond set into the caseband at 6 o’clock. The case is also endowed with a sapphire crystal back protected by a hinged dust cover bearing the hand-engraved inscription “A mon père, 85 ans de passion horlogère” (To my father, 85 years of watchmaking passion).

The sapphire crystal provides a fine view of the particularly painstaking finish lavished on the new R AL 27 PS self-winding movement.

The chamfered edges of the bridges and hammers are gilded. The 22K yellow-gold mini-rotor is rhodium plated with yellow-gold edges and adorned with a black-lacquered hand engraving reproducing Philippe Stern’s signature.

Each timepiece from this exclusive series comes with an alligator leather strap in shiny black with a platinum fold-over clasp.

Patents for Caliber R AL 27 PS

(1) Unidirectional coupling mobile (European patent EP4058853A1)

This unidirectional coupling system was designed to form the connection between the rack and the strike-work barrel drum when the strike-work barrel spring is being wound (actuation of the slide piece). On the way out, the rack winds the strike-work barrel, whereas as it returns, it disconnects from the barrel –thereby preventing the strike-work barrel spring from unwinding.

(2) Timepiece incorporating a minute repeater and an alarm, with reversible selection by the user (European patent EP4071560)

This system enables the user to choose between a “minute repeater” mode, where the watch strikes the displayed time directly after actuation of the slide piece, and an “alarm” mode, where the release of the striking work, after actuation of the slide piece, is placed on hold until the time indicated by the movement corresponds to the programmed time. This selection can be changed at will and the mechanism is designed to be insensitive to errors of manipulation.

(3) Timepiece with repeater and constant-travel slide piece (European patent EP4071561)

This mechanism ensures that the slide piece for the striking-work always travels the same distance when actuated, regardless of the striking mode selected (minute repeater or alarm) and the number of strikes to be struck, with no risk of breakage. In this way, the user knows that the striking mechanism always has sufficient “wind” once the slide piece reaches the end of its travel.

(4) Striking mechanism equipped with a delaying device (European patent EP4071562)

This system for synchronizing the racks in striking mechanisms consists of a blocking lever designed to delay the fall of the minute rack until the quarter jumper has moved towards the safety device that prevents miscounting just before a new hour begins. It ensures that the strikes always occur in the right order – hours, quarters and minutes – and therefore that the watch always chimes the correct time.

Technical details

Model: Patek Philippe Minute Repeater Alarm Reference 1938P-001

30-piece limited edition

Caliber R AL 27 PS
Self-winding mechanical movement
Minute repeater and 12- hour alarm striking the programmed time on the same two classic gongs. Small seconds
Diameter: 30 mm
Height: 8.23 mm
Number of parts: 561
Number of jewels: 47
Power reserve: Min. 43 hours – max. 48 hours
Winding rotor: Mini-rotor in rhodium-plated 22K yellow gold hand-engraved with
Philippe Stern’s signature, unidirectional winding
Frequency: 21 600 semi-oscillations per hour (3 Hz)
Balance: Gyromax®
Balance spring: Spiromax® (in Silinvar®)
Balance spring stud: Adjustable

Operating controls

3-position crown
Pushed home: manual winding
Pulled out to middle position: setting of the alarm time in 15- minute steps
Pulled out all the way: setting the time

Pusher for selection of chiming mode set into the crown at 3 o’clock

Slide piece
To actuate the minute repeater and the alarm. Set into the left flank of the case.


  • With hands: Hours and minutes from the center, Small seconds at 6 o’clock, 12-hour alarm from the center
  • By a bell-shaped aperture at 3 o’clock: Indication of chiming mode: “minute-repeater” mode (black), “alarm mode” (red), alarm actuated (white)

Patek Philippe Seal

Brilliant-cut diamond (0.02 ct) set between the lugs at 6 o’clock
Sapphire-crystal back protected by a hinged dust cover
Not water-resistant; protected against humidity and dust
Case dimensions: Diameter: 41 mm
Width (from 3 to 9 o’clock with crown): 48.16 mm
Length (across lugs): 49.4 mm
Total height (crystal to dust cover): 14.2 mm
Width between lugs: 21 mm

Dial plate in 18K gold with portrait of Philippe Stern in Grand Feu white and gray miniature painting on enamel, on a Grand Feu black enamel ground
Applied Breguet-style numerals in 18K white gold
Breguet-style hour and minute hands in 18K white gold
Breguet-style hand for the alarm time in 18K rose gold
Baton-style small-seconds hand in 18K white gold
Railway-track minute scale transfer-printed in white; small seconds dial and Patek Philippe logo transfer-printed in gray
Rose-gilt powdered quarter-hour scale for the alarm time

Alligator leather, large square scales, hand-stitched, shiny black, with platinum fold-over clasp