| 摘要 |
If the first medium frequency in a radio telephone receiver is less than the reception bandwidth multiplied by two, a faulty reproduction is generated in a mixer which cannot be filtered out by means of fixed filters in the front part of the receiver. The use of a low medium frequency is made possible, however, according to the invention, so that a voltage-controlled interphase filter 2 is connected between the RF signal wave and the circuit earth before the mixer, which filter is caused to suppress the radio frequency signal in the upper area of the reception band which causes the faulty reproduction. <IMAGE>
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