Next-generation wireless experimentation benefits from new large-scale open-access software defined radio (SDR) platforms. Each SDR's transmissions must be measured and monitored to guarantee spectrum compliance. The measured spectrum is, however, corrupted by external co-channel signals. This demo presents the Bidirectional Incident/Transmit Signal Separator (BITSS), a system which estimates the linear system model, the SDR's transmit signal, and the signals from other sources incident to the antenna, all on the fly and without a signal prior or system information. We implement and run BITSS on POWDER and evaluate its performance. The demo shows that BITSS enables separation over a range of signal parameters with high accuracy and alerts users and the operator whenever a spectrum violation occurs.