10 1/2”’ | Hand Wind | Swiss Lever | No Seconds |

Remarks:

• Base is an old version of the Felsa 71 without setting lever spring
• Cover plate made of metal -> no jewel bearings underneath!
• Here the patent refers to the shock protection, which is integrated into the corrector; this is only effective axially

 

• Listing ID: 1491
• Manufacturer / Brand: Felsa / Silena
• Caliber: Silena 10 1/2''' = Felsa 71
• Size: 10 1/2'''
• Shape: Round
• Winding: Manual (Crown)
• Hand Setting: Crown
• Seconds Hand: None
• Escapement: Lever (Swiss, English, Glashütte)
• Date & Day: None
• Jewels: 7
• Setting Lever Screw/Pin Position: Left
• Balance Position: Bottom (120 - 240°)
• Shock Protection: Silena (axially effective only)
• Beats per hour: 18,000
• Balance Type: Monometallic screw balance
• Power Reserve: Unknown
• Production Period: Unknown, probably before 1928
• Identification: Patent number 102795 engraved on the ratchet wheel, referring to the Swiss patent CH102795 from 1924 by Koch/Silena: „Rückervorrichtung für Taschenuhren“ (Corrector device for pocket watches). The newer version with setting lever spring is listed in the Ebauches SA catalog from 1928.
• External Link: https://uhrforum.de/threads/identifizierte-uhrwerke-die-weder-bei-ranfft-lorenz-noch-im-watch-wiki-zu-finden-sind.86322/page-45#post-6027262
• Country: Switzerland
• Contributor ©: Uhrforum.de member Badener (Andreas Kelz)