LOW-COST PROCEDURE TO SOLVE THE CHRONIC PROBLEM OF DARKENING OF THE GSM-19 MAGNETOMETER LCD DISPLAY SCREEN-19

Abstract

his paper presents the development and validation of an alternative corrective maintenance method applied to the chronic problem of LCD screen darkening in the Overhauser magnetometer model GSM-19, manufactured by GEM Systems Inc. The equipment is used at the Tatuoca Magnetic Observatory, located at the mouth of the Amazon River, a region characterized by a hot climate and high relative humidity throughout the year—conditions known to be unfavorable to the durability of electronic components and polymeric materials. The observed malfunction was associated with the degradation of the rear reflective film of the LCD, resulting in a progressive loss of contrast and readability. The proposed procedure consisted of the controlled disassembly of the display module, removal of the deteriorated original film, and its replacement with a new reflective layer fabricated from the internal material of Tetra Pak® carton packages (milk, juice, etc.), which are composed mainly of layers of paper, polyethylene, and aluminum, the latter providing high reflectivity. The adopted methodology emphasized low cost, material reuse, and ease of execution, without the need for original spare parts, which are often unavailable or expensive. After the intervention, the display showed full recovery of readability, adequate contrast, and operational stability during continuous field use. The results demonstrate that the proposed method is technically feasible, effective, and suitable for scientific instruments operating in harsh environments, contributing to extended service life and reduced maintenance costs for permanent magnetic observatories.