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

摘要

A device for detecting the optimum anode load impedence of a transmitter tube in a high frequency transmission chain. A phase shift circuit phase shifts by k pi /2 (with k being a positive or negative uneven integer) the phase difference between the input and output voltages of the tube. The phase shifted voltages are multiplying together in a circuit, and the mean value of the product is then calculated. Cancellation of this mean value corresponds to the anode load impedance passing through a purely resistive value. Thus, the circuit allows the phase matching detection to be made, which is independent of any modulus matching detection.