The thermal and electrical performance of the solar photovoltaic (PV) panel of a solar photovoltaic thermal (PVT) air system is determined experimentally in the present work. For this purpose, a data acquisition system was developed indigenously using ATMEL MEGA 2560 and ATMEL 328 microcontrollers. The parameters measured were PV panel surface temperature, inlet and outlet air temperatures, PV current, and voltage. The parameters were also compared with those of a reference PV system to demonstrate the effect of cooling of PV panel on its electrical power output. The experiments were performed in the locality of Tiruchirappalli, Tamilnadu, India (11 deg N latitude, 79 deg E longitude) and the working of the PV data acquisition was tested for a period of 3 months from February to April 2017. The results indicate acceptable working of the indigenously developed PV/PVT data acquisition system.