Simatupang, F. and Nainggolan, W.O. 2024. Design and Implementation of Rain Gauge Measurement using Ultrasonic Sensor HC-SR04 (Case Study using Ombrometer Method). Piston: Journal of Technical Engineering. 7, 2 (Jan. 2024), 80–90. DOI:https://doi.org/10.32493/pjte.v7i2.36619.