| 摘要 |
A mixer arrangement for obtaining an IF contains a mixer circuit (1) comprising a mixing oscillator (3) and an input circuit (5) having several inputs (E1, E2, E3). Resonant circuits (11, 12, 13), which can each be tuned over a certain frequency range, are connected to these inputs via capacitance diodes (D21, D22, D23) as coupling capacitances, and switching diodes (D1, D2, D3), connected to earth, are connected to the said inputs via isolating capacitors (C1, C2, C3). The switching diodes normally connect the inputs of the input circuit to earth with respect to RF. Only the switching diode (D3) of that input (E3) of the input circuit of which the associated resonant circuit (13) is selected for transmitting the oscillation is cut off. In the arrangement according to the invention, the barrier layer capacitance of the blocked switching diode only influences the connected resonant circuit to a much reduced extent. <IMAGE>
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