TIMEGRAPHER
The timegrapher is an instrument used to measure the instantaneous rate of watches. Although various manufacturers produce timegraphers, watchmakers have grown accustomed to referring to these devices by the name of a specific model or brand, formerly Vibrograf, and nowadays most commonly Witschi.
To take measurements, the watch (or movement) is placed on a support that can be adjusted along three axes. The clamp that holds the watch (or movement) is fitted with a microphone that picks up the impacts of the escapement (the “tick-tock” of the watch). These sounds are transmitted to the timegrapher, which compares their frequency and regularity against a built-in high-frequency resonator.
Modern timegraphers automatically detect the operating frequency of the watch. The timegrapher’s screen displays both graphical and numerical information relating to the watch’s daily rate (s/d), its amplitude, and any beat error of the balance and hairspring assembly.
In addition to verifying performance parameters, the timegrapher also helps diagnose a wide range of faults, such as escapement defects or gear train issues. With advances in computer technology and automation, such as the inclusion of automated multi-position microphone supports (covering five or six test positions), timegraphers are becoming increasingly precise, powerful, and comprehensive.
Useful links:
– Setting