Sujet
Man with a group of 100 kHz quartz crystal oscillators
Légende
Man with a group of 100 kHz quartz crystal oscillators which served as the U.S. National primary frequency standard in 1929 circa 1930
Date
01 févr. 1930
Crédit
Photo12/Universal Images Group/HUM Images
Notre référence
UMG22A04_093
Model release
Non
Property release
Non
Licence
Droits gérés
Format disponible
43,9Mo (3,1Mo) / 37,3cm x 29,5cm / 4401 x 3490 (300dpi)