HEUER Chronosplit Modules and Repairs

On this page, I discuss the original Calibre 102 watch and its variants. More information on the Chronosplit LCD can be viewed by clicking on the links above.


The Calibre 102 Chronosplit wristwatch features a 1/100 second chronograph with lap and split time with a run time of 11 hr, 59 min & 59.99 secs. For this model, Heuer adopted large-scale electronic integration (LSI) which substantially reduced the IC count from its LED predecessor. The Calibre 102 has one dedicated IC driving the top time display, and the 2nd driving the bottom chronograph display. At the time the IC reduction improved reliability however due to the delicate open wire-bonded circuit design failure was sooner or later inevitable. I discuss this in much more detail here: Typical Faults


An interesting historical fact is that Heuer produced special Ferrari Chronosplit models which were worn by famous Formula 1 drivers such as Niki Lauda & Gilles Villeneuve.


Heuer also manufactured some special Calibre 102  variants including the Ford Split Lap Unit 77 and the Kentucky R102.713.



Fig 1. A Rawsar repaired Ford Lap 77 - Featuring new Rawsar displays.

Fig 2. An original repaired Heuer Kentucky LCD-LCD Chronograph.

Fig 3. Niki Lauda sporting a R102.703 LCD-LCD Chronosplit