HEUER Chronosplit Modules and Repairs

Stage 2 - H2a Module Conversion


The purpose of Stage 2 is to recover and test the prospectively reusable original Calibre 100 Heuer Chronosplit parts to reuse both the old original Heuer LED and LCD display panels.


Once the parts have been carefully harvested from the dead module the old Chronosplit LED and LCD displays are tested to ensure they function properly and have no dead segments or digits. If the displays fully pass testing and are deemed reusable you have the option to convert your Chronosplit Calibre 100 module to a Rawsar H2a module.


Please note that the original Heuer Chronosplit displays are very old and fragile and realistically failure can happen. Faults on the LCD panel are fairly easy to determine and are often seen as "bleed" or discolouration. The LED display is more difficult to test as it has to be very carefully removed from its circuit board. Typical problems and faults that occur with the LED display are dead segments or whole digits, the root cause being broken wire bonds where de-lamination (splitting) between the substrate and epoxy lens happens. If your displays successfully pass removal and testing they can be used for the Rawsar H2a module otherwise my other modules (the H2b or H2c) can prospectively be better options.


The H2a module essentially replaces the three old Heuer PCBs with two specially-built Rawsar PCBs, one PCB for the top LCD display, and the other for the bottom LED display. The old electronics are replaced with a new modern CPU, transistors, resistors, capacitors and quartz crystal. Please see Fig. 2 & 3


The new Rawsar design also removes the need for the old & worn-out troublesome elastomer conductive strips. The Rawsar module also removes the incandescent LCD backlight and replaces it with a white LED backlight providing better and more efficient low-light viewing.


Once complete the H2a module will function and look exactly like the original Heuer Cal 100 Chronosplit module with the bonus of greater reliability.


If the repair is not successful at this point, I then move to Stage 3. The H2b Module.

Fig 1 - A Rawsar H2a module utilising the original Heuer displays

Fig 2 - Front and back view of Rawsar H2a Chronosplit module comprising of 2 circuit boards.

Chronosplit repair module - Rawsar h2a Front Chronosplit repair module - Rawsar h2a Back

Fig 3 - Fitment of Rawsar H2a to the original Heuer Cal.100 Chronosplit case

Chronosplit repair module - Rawsar h2a Fitting 1 Chronosplit repair module - Rawsar h2a Fitting 2 Chronosplit repair module - Rawsar h2a Fitting 3

On the next couple of pages I offer further repair options to cover display failure scenarios.


For more information on the H2a module please send an email to support@rawsar.com