Clarifying radio receiver

Claim 1

A radio receiver having a digital processor controlled signal clarifier, said radio receiver comprising: (a) mixer means having inputs coupled to simultaneously receive (1) input signals comprised of a plurality of spaced apart frequency channels and (2) mixing frequency signals of a first selectable frequency, for generating in response thereto, output signals in which said input signal is shifted in frequency such that the center frequency of a selected one of said frequency channels is shifted to a predetermined frequency; (b) mixing frequency generator means having inputs coupled to receive first digital coded signals identifying said first selectable frequency for generating said mixing frequency signals of said first selectable frequency in response thereto; (c) a charge transfer device transversal filter means having a selectively controllable passbandwidth centered about a finely tuneable center frequency, said filter means being coupled to said mixer means for defining a selected frequency band of said output signals to pass only said selected frequency band of said selected one of said frequency channels, said filter being coupled to receive simultaneously with said output signals, filter clocking signals of a second selectable frequency, said filter means being responsive to said filter clocking signal for controlling the passbandwidth and finely tuneable center frequency of said filter means in response to the frequency of said clocking signal; (d) filter clocking signal generator means having inputs coupled to receive second digital coded signals identifying said second selectable frequency for generating said filter clocking signals of said second selectable frequency in response thereto; (e) keyboard means having a plurality of channel selection keys, at least one band selection key and at least one clarify key; and (f) digital processor means coupled to said keyboard means and to said mixing frequency and filter clocking signal generators, said digital processor means being responsive to actuation of said channel selection keys for generating said first digital coded signals, being responsive to activation of said at least one band selection key for computing the passbandwidth and center frequency of said filter means and for generating said second digital coded signals in accordance with the computed passbandwidth and center frequency and being responsive to said at least one clarify key for altering the computed center frequency of said filter means in fine increments and for generating said second digital coded signals in accordance with the altered center frequency.