This article reports the development of a direction-finding (DF) system and channel sounder, at 5.8 GHz, by a team of undergraduate and graduate students from the University of Alabama, Tuscaloosa, for the 2018 IEEE Antennas and Propagation Society (AP-S) Student Design Contest. Based on the competition's transmitter (Tx) specifications, a link budget was calculated to determine the components of a receiving-antenna system. Accordingly, a low-cost, small, battery-powered software-defined radio (SDR) based on a pseudo-Doppler antenna array (PDAA) receiving system was constructed using a HackRF One (HO) SDR, an Opera Cake (OC) switching board, and a circular array of omnidirectional monopoles (the PDAA). For digital signal processing, GNU Radio software was used.