You do not need a soldering iron, but you do need precision.
Turn it one degree at a time. We are talking movements so small the human eye can barely register them. A full rotation of 360 degrees equals about 1000 Ohms change. So: ps2 fat laser calibration
Calibrating the PS2 Fat laser requires patience and attention to detail. Follow these steps carefully: You do not need a soldering iron, but you do need precision