26 jewel accutron movement with ETA adjustment screw

This is odd. I have a Sellita movement that adjusts via a lever that must be pushed to either + or - to regulate speed. I recently purchased a 65B001 accutron automatic with 26 jewels yet it has the screw type adjustment found on ETA movements. The second hand seems much smoother as well. What exactly do I have. I’m confused at this point. Was this a transitional movement or what? Does anyone know? Please help me figure this out. Thx, Jonathan Williams. 

Reverend Rob's picture
Reverend Rob
Posted November 10, 2017 - 10:40am

Panel Member

Not all ETA movts have the eccentric screw to adjust rate, and there were many variations in this over the years. The most common adjustment is the other one you describe, simply to move the rate pin carrier by carefully pushing it. Sometimes there will be a pointer on the top of the balance bridge, sometimes not. Sellita manufactured ETA designs by contract, but as the patents are now in teh public domain, anyone can make a 2824, for example. Some Sellita movts are superior to their ETA equivalents, like the 2892. Sellita refined the train bridge and made it easier to adjust the jewels in the chronometer versions of this movt.