Measuring balance wheel amplitude with MicroSet Watch Timer Pro

The MicroSet Watch Timer Pro allows you to measure the amplitude of vibration of a watch balance wheel to a high degree of accuracy.

A watch tick is composed of at least three main sources of sound (there are two additional sounds of lesser importance):

  • the unlocking
  • the impulse
  • the drop

The amplitude of a balance wheel can be calculated from the geometry of the escapement and the relationship of sounds within the tick. Specifically, the interval of time between the unlocking and the drop is used with the beat time and lift angle to calculate a value for the amplitude.

The image at the right is taken from an oscilloscope set up to capture the complex sound of a single watch tick. The three sound bursts can be clearly seen.

 

The Watch Timer Pro has an "oscilloscope mode" to analyze a watch tick in detail. This feature works in conjunction with the Windows interface software. The image below shows the function at work. The three primary components of a watch tick are clearly seen. The computer has analyzed the parameters and tells us that the amplitude of the balance wheel in this watch is 262 degrees.

 

The Watch Timer Pro can even record the balance wheel amplitude over time so you can see how it changes. No other watch timer on the market has this ability.