MODEL RELEASED. Circuit testing. An engineer checks current flow through circuit boards at a telephone exchange. He is holding a voltmeter. Most modern exchanges use solid-state devices to carry out the switching process,with computers to control the operation | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Tompkinson, Geoff |
Taille de l’image : | 4236 px × 4921 px |
Model Release : | Disponible |
Property Release : | Non requis |
Restrictions : | - |