Created in the 19th Century, GMT, Greenwich Mean Time, originally referred to mean solar time at the Royal Observatory in Greenwich, London. Already used by the British navy to calculate their longitude position from the Greenwich meridian, it was introduced in the United Kingdom by the Railway Clearing House in 1847. It was then legally adopted as official time throughout Great Britain in 1880, and then in the entire world for the major part of the 20th Century, before being replaced in 1972 by UTC, Universal Time Coordinate.
GMT is usually used in the watch making world to designate watches with a second time zone. The two time measurements, even though close, do not coincide as GMT is based on terrestrial rotation, while UTC on atomic international time. UTC offers today a modern view of time zone division, for the majority, in full hours, directly linked to the real rotation of the earth and only slightly variable.
F.P.Journe innovates once again with the presentation of the Octa UTC ®, patented system that faithfully takes us back to the modern standards of determining time zones in full hours. Mechanically it indicates the different time periods linked with the earth's geographical positions, indicating summer and winter hour.
On the dial, the main hours are indicated by the blue hands, and linked to the calendar indicating the main geographical time. The rose gold hand indicates the time zones on 24 hours, represented by the earth's 24 time zones.
UTILIZATION
The time of the main geographical place is set by pushing the small secured pusher at 4h00. After having pulled the crown in position 2, the wearer is positions the second geographical region on 0 for winter hour. The gold hand is automatically and simultaneously positions itself at the corresponding time of this region. The +1 / -1 graduations' purpose is to position the specific region for summer hour linked to the geographical location of the user, depending if it's positioned east or west of the chosen zone.
The mechanical movement with automatic winding is manufactured in 18K rose gold, like all F.P.Journe –Invenit et Fecit watch creations. It is constructed on the 1300.3 calibre, and offers an additional complication to the Octa line, still in the same calibre dimensions. The dial features off centre hours, minutes and seconds, a retrograde power reserve, a large date, and for the first time, a dial with the earth divided in time zones. The passing of the months from 28 to 31 days is done manually.
The OCTA UTC also features the 22K red gold exclusive off centre rotor that winds in one direction only, thanks to a self-blocking ceramic ball bearing exclusive system. Every infinitesimal movement is thus maximally exploited for an optimized winding of the watch.
In 2001, F.P.Journe presented the OCTA collection composed of mechanical wristwatches with automatic winding featuring an exceptional power reserve of 5 days (120h), all with the same case thickness regardless of the complication.
Technical Specification - OCTA UTC
Movement :
- Automatic Calibre FPJ 1300-3 in 18K rose gold (4N)
- Unidirectional automatic winding
- Off-centre 22K gold guilloché winding rotor
Three position crown:
- Correction of 24h time zones in position 2, clockwise
- Correction of date in position 2, anti clockwise and Correction of time in position 3
- Instant jump calendar
- Rotation of the earth by secured correction pusher at 4h
Number of jewels : 40
Dimensions of the movement:
- Overall diameter : 30.80 mm
- Casing-up diameter : 30.40 mm
- Overall height : 5.85 mm
- Height of winding stem : 3.00 mm
- Diameter of stem thread : S0.90 mm
Indications:
- Off centre hours and minutes / off centre timezones / Small second at 4h30 / Earth dial divided in timezones at 7h30 / winter summer hour / large date / power reserve at 9h
Decoration :
- Circular Côtes de Genève on 18K gold bridges
- Circular graining on 18K gold baseplate
- Polished screw heads with chamfered slots
- Chamfered and circular grained wheels, diamond-moulded
- Pegs with polished rounded ends
Escapement : Escapement 15 tooth
Balance :
- Four adjustable inertia weights
- Anachron free-sprung flat balance spring
- Mobile stud holder
- Nivatronic laser soldered balance spring
- Pinned GE stud
- Frequency : 21'600 Alt/h, 3 Hz
- Inertia : 10.10 mgcm2
- Angle of lift : 52°
- Amplitude : 0 h à plat : > 300°
- 24 h à plat : > 280°
- Autonomy : 120+/- 12heures
Dial :
- Whiter or red gold
- Hours and minutes, small second in silvered guilloché
- Date display in silver
Case:
- Platinum or red 18K gold
- Diameter : 38 or 40 mm
- Height : 10.6 mm
Number of parts :
- Movement without dial: 301
- Cased up with strap : 342
Winding Speed : 274 anti clock-wise rotations per 24 hours
