(under subclass 230) Subject matter including significant means for controlling the extent to which the receiver is capable of differentiating between a desired signal and disturbances of the other frequencies or whereby the difference between the limiting frequencies of a band of frequencies over which the receiver is operative may be varied.
SEE OR SEARCH THIS CLASS, SUBCLASS:
193.1, and 289, for systems comprising the combination of receiver systems with input wave selection means.
SEE OR SEARCH CLASS
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems,
39+, for miscellaneous frequency comparing, selecting, or detecting circuits.
333, Wave Transmission Lines and Networks 167+, for passive wave filters which may be of the adjustable bandwidth type, especially subclasses 177+ for transformer coupled type (e.g., intermediate frequency transformers).
334, Tuners, particularly
40, for tuners with sensitivity or "Q" adjustment means.
