[en] The authors have built a number of inexpensive, nuclear-spectroscopy-based, first-generation, computerized tomography (CT) scanners to satisfy CT inspection requirements. This paper describes these CT scanners in detail and discusses their advantages and disadvantages when compared to the more common, higher-generation, current-integration-based scanners. The major advantage of nuclear-spectroscopy-based scanners is that they can be used to determine an internal, spatially distributed, effective-atomic-number and density map within the object. The authors also show how these scanners can be used to acquire meaningful chemical information for nondestructive characterization of materials and dimensional information for evaluating assembled components