SPT - Citizen Shutter

This technical manual provides comprehensive service and repair procedures for the Citizen shutter used on the Petri 7S camera. Authored specifically Amos for the Society of Photo-Technologists, it serves as an essential reference for professional camera repair technicians. The publication includes shutter speed and synchronization test results, with measurements taken across multiple speed settings ranging from 1/1 to 1/500, enabling technicians to assess performance accuracy. The guide details disassembly and reassembly procedures for critical components including the photo cell, retaining ring, front cup assembly, and scalloped ring. Step-by-step procedures address internal mechanism access, removal of the retard assembly, time delay gear train extraction, and front and back side disassembly. Annotated photographs clearly identify major shutter components such as the shutter speed cam detent, release lever, and photo cell contacts. The manual is accompanied by detailed illustrations showing the shutter mechanisms at various stages of disassembly, enabling technicians to understand the spatial relationships between components. Coverage extends to specialized tools required for safe removal of certain pins and mechanisms, emphasizing proper technique to prevent damage. This resource is indispensable for professional repair technicians and vintage camera enthusiasts undertaking restoration or maintenance of this classic shutter mechanism with precision and professional standards.