Television transmitter comprising a common klystron for picture and sound

摘要

1. A television transmitter comprising a common klystron for image and audio characterized in that it comprises : - a klystron (10) whose one output cavity (16) is coupled with the output of the transmitter ; - means (9) to supply one klystron electron beam density control electrode (12) with an impulse signal for amplitude, duration and cycle such that the klystron (10) is able to supply a power equal to its peak power during time intervals corresponding to the sync surges of the image signal and such that the klystron (10) is only able to supply a given fraction of its peak power during the remainder of the time, such fraction corresponding to the power to be supplied during the image signal suppression porch ; - means (21) for negatively modulating the amplitude of an intermediate frequency signal by a video signal ; - means (4) for generating at least a second modulated intermediate frequency signal modulated by a video signal ; - correcting means (7 and 8) in order to modify the group delay and the amplitude of each second intermediate frequency signal, for compensating the variation in the group delay and the variation in amplitude of the signal supplied by the output cavity (16) of the klystron (10), these variations being caused by the electron beam density control ; - and means (6) for adding the first intermediate frequency signal and the second intermediate frequency signal as corrected by the correcting means (7 and 8), for transposing the resulting signal to a very high frequency and for passing it to the input cavity (14) of the klystron (10).