The Payload for Ultrahigh Energy Observations (PUEO) is a long-duration balloon experiment designed to observe ultra-high energy neutrinos with energies above 1 EeV. Penn State's role in the project, led by Dr. Stephanie Wissel, is to provide ground calibration. In-flight calibration from the ground is necessary in order to compare the data collected with sensor responses to known signal inputs. Sean Golder is working on consolidating the ground-cal boxes and building the internal timing boxes. Elise Beishline is programming a pulse-counting microcontroller and using it to power an antenna switch. The Payload for Ultrahigh Energy Observations will launch over Antarctica in December, 2025.