An apparatus and method for detecting radio frequency transmit power levels produced by a power amplifier of a wireless device is described. In one exemplary apparatus implementation, the apparatus includes a power amplifier, an antenna switch and a power amplifier detector. The power amplifier is configured to amplify a transmit signal at a desired power level. An antenna switch, is located between the power amplifier and an antenna, and is configured to switch the antenna from a receive mode to a transmit mode and vice versa. A power amplifier detector is connected to the antenna switch. The power amplifier detector is configured to receive a leakage signal from the antenna switch as a basis to detect the power level of the transmit signal.