Abstract: A radio-frequency amplifier incorporating at least one amplifing device comprises means for applying to the device a signal related to changes in the radio frequency power handled by the device, thereby to compensate for changes in the conduction point of the device due to temperature changes within the structure of the device resulting from changes in the radio frequency power handled by the device.

Abstract: A circuit is provided for precorrecting an aural carrier signal in a common amplifier system in a television transmitter wherein an aural frequency signal and a visual signal are commonly amplified. The precorrecting serves to minimize cross-modulation distortion of the aural carrier caused by the common amplification. A visual carrier signal is modulated by a video baseband signal to provide a modulated video signal from which there is provided a sampled video signal. This sampled video signal is supplied to an aural corrector which provides from the sampled video signal a phase correction signal and an amplitude correction signal. The phase correction signal and amplitude correction signal are used to modulate an aural carrier signal to provide a precorrected aural signal which is then combined with the video signal to provide a combined signal.