Vibrations per hour

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Vibrations per hour (vph, VPH) is a mechanical timepiece specification. It is used to express the frequency of a watch movement. [1] [2] VPH describes the number of times that a vibrating timekeeping component completes a vibration cycle in 1 hour. [3] More vibrations per hour yields higher timekeeping resolution, and usually indicates a higher precision mechanical movement. [4]

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The Bozeman Watch Company of Bozeman, Montana, was an American company that designed and engineered its own timepieces and had its mechanical components certified by the Contrôle officiel suisse des Chronomètres (COSC) certified timepieces. The company went out of business in 2015.

References

  1. Fritts, C.E. (1904). The Watch Adjuster's Manual. The Keystone. p.  81 . Retrieved 13 September 2018.
  2. "Vibration, VPH". WatchTime – USA's No.1 Watch Magazine. Retrieved 8 July 2018.
  3. Doerr, Elizabeth. "The Slowest Watch in the World". Forbes. Retrieved 8 July 2018.
  4. "Vibration, VPH" . Retrieved 31 August 2013.