GOSSEN - Ajusting Gossen Lunasix

Comprehensive service manual for adjusting and maintaining the Gossen Lunasix exposure meter. This workshop guide explains all five accessible tuning points on the Lunasix, a precision light meter trusted by professional photographers for its dependable accuracy in the field. The manual covers complete disassembly procedures, including safe removal of the meter's top housing and careful access to the internal circuit board. You'll find detailed operation notes on the dual-range circuit design (high and low range) with its two potentiometers and three variable resistors. Calibration procedures include battery circuit testing through variable resistor R1, low-range correction using Lo 1 and Lo 2 adjustments to fix reading linearity across the scale, and high-range tuning via Hi 1 and Hi 2 for consistent accuracy at both ends of the measurement scale. Electrical schematics show current flow paths, contact points, and ground return routing so you understand exactly what each adjustment affects. The guide also presents a streamlined method for regular users who want to document and maintain personal reference schematics specific to their own meter. Throughout, the manual stresses using fresh batteries during all adjustment work and provides step-by-step instructions for each tuning procedure, ensuring precision in your adjustments and preventing unwanted drift in either operating range.