This research was carried out with the aim of explaining the implementation of a mobile-based legal metrology service system for employees and improving the quality of services for legal metrology at the Jombang Regency Office of Trade and Industry. With this mobile-based legal metrology service application, it can make it easy for employees to see the calibration and re-calibration schedule sent by the central metrology website and employees can send the results of the test and re-calibration directly in real-time without having to come to the metrology office. This research applies the waterfall method in its development, which is a systematic and structured approach involving a series of sequential stages. The results of this research created a mobile-based application for employees of the Jombang Regency Trade and Industry Office.
 
 

In the digital age, public road lighting (PJU) monitoring efficiency is becoming essential for effective infrastructure management. The research developed a PJU monitoring system based on LoRa technology and an Arduino microcontroller to monitor the operating conditions of PJU solar panels in real time. The system uses the LoRa 433 MHz module for remote data communication and is equipped with a voltage sensor to monitor batteries and solar panels as well as an ACS712 current sensor to measure current consumption on LED lights. The data is displayed on an I2C 16x2 LCD screen, making monitoring easy. LoRa technology offers the advantages of broad communication range and low power consumption. The development method used is prototyping, including needs analysis, system design, implementation, testing, and maintenance. Test results show that the system works well, with sensors providing adequate accuracy and LoRa communication enabling remote data access. The system improves the efficiency and accuracy of PJU monitoring, as well as reduces time and effort in the monitoring process. Overall, the system is an effective solution for PJU management in the digital age.