The Lorsa 8FB is an only in details modified successor of the caliber Lorsa 8FA, so it’s a rather large form movement for ladies’ watches, which beats with 21600 A/h.
It probably dates from the late 1970ies or early 1980ies.
The only difference to the Lorsa 8FA. On the caliber 8FB, there’s an additional surrounding around the holes. Everything else remains the same.
Timegrapher resultThe specimen shown here is NOS and unregulated, but might have sat for 30-40 years in the drawer. Nevertheless, the timegrapher rates are mostly very will, except on 9O, which cannot be explained:<br/>
|dial up||+10 s/d||285°||1.9ms|
|dial down||+4 s/d||274°||1.9ms|
|crown right (12 up)||+1 s/d||240°||1.6ms|
|crown up (3 up)||+20 s/d||230°||2.3ms|
|crown left (6 up)||-18 s/d||231°||2.6ms|
|crown down (9 up)||-85 s/d||239°||2.0ms|
|Number of jewels:||17|
Nickel anular balance|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Hairspring key|
|Construction type:||solid construction|
|Winding mechanism:||yoke winding system|
|Setting lever spring:||6 hole(s)|
|Size:||6 3/4 x 8''' (measured: 15,2 x 17,9mm)|