2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/84202We present two experiments in closed-loop feedback control. In the first experiment, students control the pointing angle of a laser to "lock" the laser onto a "target." In the second, students stabilize the pathlength difference in two arms of a Michelson interferometer. These experiments are appropriate for electronics and optics laboratory classes for junior and senior level students.6 pages, LaTeX, submitted to Am. J. PhysPhysics EducationOpticstext