Device for detecting the optimum anode load impedance of a tube transmitter in a high frequency transmission chain

A device for detecting the optimum anode load impedence of a transmitter tube in a high frequency transmitting chain, this transmitting chain comprising besides the tube, a transmitting antenna, the device comprising a variable impedence matching cell interposed between the tube and the transmitting antenna, said cell detecting said optimum anode load impedence of said tube, by detecting, from an input and an output voltage of said tube, during the variation of the impedence presented to said anode of said tube by said matching cell, a passing of said anode load impedence through a pre-determined purely resistive value;

• said cell comprising means for phase shifting by k(.pi./2)(with k being a positive or negative uneven integer) the phase difference between said input and output voltages of said tube, means for multiplying by each other the two voltages thus processed, and means for calculating the mean value of the product thus obtained, and for cancelling this mean value, during the variation of the impedence matching cell corresponding to the passing of the anode load impedence through a purely resistive value.