Automatic distortion correction circuit for TV transmitter - samples TV signal during test portions and adjusts parameters of correction amplifier accordingly

摘要

The distortion correction circuit has a level correction circuit connected prior to the transmitter amplifiers and having twelve independently variable parameter characteristics controlled by a control circuit in turn controlled by a process circuit. Three detection circuits under the control of the process circuit sample the signal respectively at the input and output of the correction circuit and the amplifier output in accordance with synchronising pulses applied to the process circuit. Sampling is effected at the instant of transmission of test signals in the t.v. signal, the sampled results being fed to the process circuit. The latter controls the control circuit and thus the variable parameters of the correction circuit in dependence on the sampled values. The process circuit is a microprocessor.