A test device determines a Global Navigation Satellite System (GNSS) signal propagation delay in a GNSS signal distribution system (GSDS) for a radio access network. The test device includes a GNSS receiver and a clock. The GNSS receiver is connected at different times to a reference GSDS with a known signal propagation delay and to a device under test (DUT), including a second GSDS having an unknown signal propagation delay. One pulse per second (1PPS) signals are generated by the GNSS receiver and are compared to determine the unknown signal propagation delay of the DUT.