Calibration is a fundamental process aimed at refining the precision of Survey instruments. The primary objective of the EDM baseline calibration check at Yangthang is to validate the accuracy and consistency of distance measurements. The calibration procedure follows a stringent set of steps, often outlined by NLCS calibration facilities. The quarterly calibration schedule will be communicated by NLCS through social media channels one month in advance. Instruments should be submitted to the Instruments Section of NLCS a week prior to the scheduled calibration date. Requests for calibration should be routed through the Director of DoSAM at NLCS.