Junghans had several years of experimence with electromechanical movements in clocks (Ato-Mat), when they finally developed an electromechanical wristwatch movement, the caliber 600.00, which was launched in 1967.
Unlike most other electromechanical movements at that time, Junghans already used a contact free coil system with a transistor and so enhanced the reliabilty and the durability of the movement. It also was fully jewelled (17 jewels) and had an excenter regulation mechanism.
1972, the most advanced version of this movement, Cal 600.12, was lauched. It now offered a date and a new transmission mechanism from the balance over an almost traditional jewelled lever escapment to a new constructed gear.
Unfortunately, those sophisticated and expensive movement got much competition from simpler and cheaper japanese and electromechanical Timex watches, and so, today, these Ato-Chron movements are very hard to find.
This one was treatened badly by its former owner and/or his watchmaker, as you can see on the scan. It only runs in position “dial down”, probably to a broken balance staff. But nevertheless, it is still a very fascinating movement.
|Number of jewels:||17|
|Balance bearing / direction hairspring:||Counterclockwise|
Flume: K3 292|
|Mentioning in literature (years):||1971|