The the late 1960ies, Omega released the mens' watch caliber 613.
It is based on the highly successful caliber series 550, which was available since the late 1950ies, and it is more or less the caliber 563 without selfwindig mechanism. The swan-neck regulator was replaces by a slightly cheaper excenter regulator.
The construction is a classical one with a gear cock, which houses escapement wheel, fourth wheel and third wheel, which also acts as intermediate wheel for the indirect center second indication. This center second gear is located under an own cock. The rater large four-arm annular balance, made of Beryllium-Bronze beats with rather slow 19800 A/h, but together with the large mainspring barrel, it enables a really great power reserve of 50 hours.
A speciality is the red-gold-tone of the movement and its date quickset mechanism: By pulling the crown beyone the time setting position, the date jumps one day in advance. The regular date change happens slowly between 23 and 24 o’clock.
|Size:||12 1/4''' (measured: 27,9mm)|
|Number of jewels:||17|
Beryllium bronze anular balance|
|Balance bearing / direction hairspring:||Clockwise|
|Construction type:||solid construction|
|Winding mechanism:||yoke winding system|
|Setting lever spring:||4 hole(s)|