Finnegan, Henderson, Farabow, Garrett & Dunner, L.L.P.
Heterodyne receiver
 A heterodyne receiver of the present invention is of a heterodyne system including a voltage controlled circuit and a phase locked loop circuit. The receiver further includes a tuned voltage signal compensating circuit adapted to deliver a frequency passband compensating signal to a bandpass filter on the basis of a variation of an output signal obtained as a result of comparison made between a tuned voltage signal from the phase locked loop circuit and a detected signal from a detector. The heterodyne circuit can obtain a stable nearby frequency selectivity characteristic even in the case where there arises a temperature variation in the receiver. 
Kabushiki Kaisha Toshiba
H H
H04B H04B
additional inventional
Masahisa
Saito