Electronic tuning receiver
AssigneeToko, Inc.
InventorHajime Yokoyama
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Abstract
A receiver equipped with an electronic tuning circuit which uses voltage-variable reactance elements such as variable-capacitance diodes or the like in the radio-frequency tuning circuit and oscillation tuning circuit thereof. The oscillation tuning circuit includes a novel padding capacitor constituted by a composite circuit of a variable-capacitance diode and fixed capacitors connected at the position where a conventional padding capacitor is connected. With such an arrangement, it is possible to make tracking error negligibly small over a frequency band ranging from a low receiving frequency to a high receiving frequency, by applying a tuning voltage to the composite padding capacitor.
Claims3
An electronic tuning receiver comprising a radio-frequency tuning circuit and an oscillation tuning circuit including a first and a second voltage-variable reactance element, an oscillation coil, a first capacitor connected in parallel with said oscillation coil, and a padding capacitor provided in the form of a composite circuit, said padding capacitor containing a second capacitor connected in series with said oscillation coil, said first voltage-variable reactance element, and a third capacitor connected parallel with at least one of said second capacitor and a first voltage-variable reactance element, the capacitance of said padding capacitor being variable over a frequency band ranging from a low receiving frequency to a high receiving frequency, by changing the capacitance of said first voltage-variable reactance element with that of said second voltage-variable reactance element.
Dependencies are inferred from the claim text.