This quick demonstration shows in real-time how phase relationships change based on the relative position of antennas. The phase-coherent digital downconverters (DDCs) in a 6 Series MSO oscilloscope are used to observe phase differences on multiple channels. A TSG4106A RF signal generator with an antenna is used as a low-power transmitter. The 6 Series MSO is equipped with two antennas, and the transmitting antenna is moved between them. 4 and 5 Series MSOs may also be used in this application.