The Master Memovox with black dial and open case back appeared for the first time in the 2000/2001 Jaeger-LeCoultre catalogue. In the catalogue before, 1998/1999 the Master Memovox with Calibre 914 was featured with silver dial and closed case back.
Up until today, this is the only Memovox with open case back.
Due to its modest size of 36 mm in diameter and black glossy dial with red details, this watch is the one of all my Memovox, that makes the ladies to look closer, show interest… Not always a good thing, currently this one is “under siege” of my wife (hence the pink nato)…
Through the case back you can see the hammer (the triangle shape with two screws) which when the alarm goes off strikes the free hanging gong which is attached to the crystal (the round plate with two screws).
The sound of the Calibre 914 is much more like a school bell than a cricket due to its construction. Rounder and not as strong as in earlier Memovox.
One day I will try to make a video showing the hammer in action.