| 摘要 |
A circuit arrangement for converting high frequencies to intermediate frequencies by mixing with a heterodyne frequency, wherein the high frequency signal input is connected to the signal output of the circuit arrangement via the primary winding of a polarity reversing transformer which is controlled such that the high frequency input signal appears at the signal output, alternatingly once directly and once with reversed polarity in the rhythm of the heterodyne frequency, and thus the high frequency signal is mixed with the heterodyne frequency. The polarity reversal is controlled by alternatingly opening and short-circuiting the secondary winding of the polarity reversing transformer in push-pull with the center tap of the primary winding by means of electronic switching circuits responsive to the heterodyne frequency.
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