Patent ID: 6681102
Filing Date: 2004-01-20
Classification: H03B,H03J

Abstract:
A radio transmitter and/or receiver, comprising:an oscillator tuning circuit including an adjustable capacitor whose capacitance is adjustable in accordance with a first tuning signal; a filter tuning circuit including an adjustable capacitor whose capacitance is adjustable in accordance with a second tuning signal; an oscillator whose operational frequency is dependent on the reactance of the oscillator tuning circuit; a filter for filtering signals in the course of transmission and/or reception, and whose response is dependent on the reactance of the filter tuning circuit; and a tuning unit for generating the first and second tuning signals, wherein at least a part of the filter tuning circuit is a replica of a plurality of selectively engageable reactive elements of the oscillator tuning circuit on which the reactance of the oscillator tuning circuit is dependent, and the tuning unit is capable of generating one of the first and second tuning signals from the other of the first and second tuning signals, and wherein each of the reactive elements of the oscillator tuning circuit is selectively engageable by a respective oscillator tuning switch connected in series therewith.