FHF 691 (Standard)

FHF 691 (Standard) | 17jewels.info - The Movement Archive

FHF 691 (Standard)


The “Standard” caliber 691 of the Fabrique d’Horlogerie de Fontainemelon bases on the common FHF caliber 69 and added a center second hand to it.

Since the available space is very low on these form movements, the FHF had to use an extraordinary solution: The fourth wheel indirectly drives a wheel on the top of the main plate, which itselfs drives the center second pinion.

The rest of the caliber 691 is identical to the FHF caliber 69.

FHF 691 (Standard): Center second hand driving mechanism

Center second hand driving mechanism

FHF 691 (Standard): FHF 691 dial side

FHF 691 dial side

Technical data

Caliber:691 (ST)
Size:6 1/4 x 8'''
Number of jewels:17
Escapement:Pallet lever
Balance types: Nickel anular balance
Shock protection(s): Incabloc
Balance bearing / direction hairspring:Counterclockwise
Moveable stud:yes
Adjust mechanism:Fonto
  • lever
  • escape wheel, seconds wheel, third wheel, center minute wheel
  • center second pinion
  • mainspring barrel
Winding mechanism:yoke winding system
Setting lever spring:4 hole(s)
  • SCI (indirect center seconds)

Usage gallery

FHF 691 (Standard): Mirexal ladies' watch

Mirexal ladies' watch