Method of automatically optimizing the recording bias for a video signal, and arrangement for carrying out the method

摘要

In recording systems in which video and audio signals are recorded in tape layers having different depths, a method and apparatus is provided which serves to ensure that the video recording bias for a video signal is always selected and adjusted for optimum results, allowance being made for an audio signal already recorded in the same tracks and for tolerances of the record carrier, the heads and the head amplifier with respect to the playback sensitivity. During recording of the video signal, the video recording bias is varied step-wise. After every change in the video recording bias, a d.c. signal is derived from the playback envelope of the audio signal, the value of the d.c. signal being a measure of the playback amplitude of the audio signal. As soon as the d.c. signal value has reached a predetermined minimum value, the video recording bias is ceased to be changed and the last value of the video recording bias is stored for the next recording process.