GOSSEN - Ajusting Gossen Lunasix

Comprehensive technical guide for adjustment and maintenance of the Gossen Lunasix exposure meter. This manual explains all five accessible tuning points on the Lunasix, a precision exposure measuring device relied upon by professional photographers for its pinpoint accuracy. The guide covers the complete disassembly procedure, including safe removal of the meter's top housing section and access to the internal circuit board. It details the operation of the dual-range circuit design (high and low range) featuring two potentiometers and three variable resistors. Calibration procedures include: battery circuit testing via variable resistor R1, low-range adjustment using Lo 1 and Lo 2 to correct reading linearity, and high-range adjustment using Hi 1 and Hi 2 for accuracy at both scale ends. The document provides explicit electrical schematics illustrating current flow, contact points, and ground return paths. A simplified method is presented for frequent users, allowing them to maintain personal reference schematics for their specific meter. The guide emphasizes the importance of using fresh batteries during adjustments and provides detailed step-by-step instructions for each tuning procedure, ensuring that only the intended adjustment is affected within each operating range.