摘要 |
A mixer circuit in which resonance characteristics of a resonance circuit coupled to the RF input terminal are prevented from entering the mixer circuit, and in which negative resistance characteristics in the local oscillator circuit are prevented from causing spurious oscillations in the mixer circuit. The mixer circuit comprises a main strip line connecting an RF input terminal to an output terminal through a frequency mixing diode and a low pass filter. The IF signal is short circuited where the mixer diode is connected to the main strip line, by a high frequency short-circuiting technique. An IF interrupt circuit is provided in the main strip line near the RF input. A resistor ended low pass filter is connected between the RF terminal and the IF interruption circuit. The local oscillator includes a strip line having a length equal to one quarter of the wavelength of the spurious oscillation which is to be prevented.
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