High frequency interference-cut filter circuit

Abstract

Disclosed is a high frequency apparatus which eliminates an influence of interfering signals. An interference-cut filter () for eliminating interfering signals is disposed between an input terminal () and a mixer (). The interference-cut filter () is so controlled that it effectively demonstrates the function while the interfering signals are transmitted. Control of the interference-cut filter () is made by a switch (), which is controlled by a selector switch controller (), and the switch controller () is controlled responsive to an error correction counter () and a radio wave transmitted from a cellular telephone (). This structure eliminates interference attributable to communication signals transmitted by the cellular telephone () and undesirable signals entering from the outside. The invention can thus realize high quality reception.