7 jewels and 1/100th of second
In 1916, HEUER brings a major evolution in watchmaking industry by creating the mikrograph and the mikrosplit, the first mecanical 1/100th timers. They feature calibers 601 and 604, very hight-end 17 and 18 jewels movements (which are then replaced by a modified Valjoux 76).
Few years laters, with the ref. 920, HEUER succeed to reach a such precision with a classical 7 jewel movement (probably a 736 one, released in 1936). The ref. 920 stays for around two decades in HEUER catalogs and commercial documents. First apparition is found in a late 30’s catalog. From the end of the 50’s, it is gradually replaced by the new “century line” 1/100th second models ( ref. 33.220, 403.220, 503.220) .
A french touch version
The model photographed above is a S.A.V.I.C version, made for the french market, probably from the 50’s or 60’s. It lightly differs from standart ref. 920 timers pictured in commercial documentation. The dial displays the name of the former french HEUER devices importer followed by the mention “Fab. Suisse”, two usual specificities found on most products handled by S.A.V.I.C (see here for more information). This stopwatch also has a very rare blue hexagonal HEUER label, attached to the loop with a thin string. Hexagonal shape and blue color are two visual elements strongly linked to France. It’s pretty possible this small card comes only with HEUER products marketed in France.
HEUER ref. 920 – S.A.V.I.C version
- start, stop and reset to zero by consecutive depression of the crown
Recorder and register
- 1/100em second recorder (long hand makes one revolution in 3 seconds)
- small 0-3 minute register (small hand makes one revolution in 3 minutes)
50’s / 60’s
- probably a 736 caliber
- 7 jewels
- unbreakable mainspring
approximately 49 mm without crown