A system for testing a communications device includes a portable wireless communications device comprising a transmitter for transmitting an RF signal. A monitoring device receives the RF signals from the portable wireless communications device and analyzes the RF signals to determine total radiated power emitted from the transmitter. An adaptive antenna equivalent circuit is coupled to the transmitter. A connection line extends between the adaptive antenna equivalent circuit and the monitoring device. The adaptive antenna equivalent circuit has an equivalent antenna impedance matched to the portable wireless communications device and the connection line and monitoring device based on transmit frequency to ensure that total radiated power of the RF signals is transmitted from the transmitter to the monitoring device.