An encoded television signal is transmitted in the form of an inverted video component amplitude modulating an RF carrier to a selected percentage of modulation and characterized by inverted reference black and white level components. At the receiver, a decoding signal equal in frequency to and 180 degrees out of phase with the RF carrier is generated and combined with the received signal to provide a decoded television signal. The level of the decoding signal is controlled in response to the difference between the peak detected reference level signals such that the percentage of modulation of the decoded television signal is the same as that characterizing the encoded signal.