| 摘要 |
1287923 Frequency changers TELEFUNKEN PATENTVERWERTUNGS GmbH 11 Dec 1969 [12 Dec 1968] 60422/69 Heading H3F A mixing stage comprises switchable non- linear devices 4a, 4b followed by a circuit, e.g. of inductors 5a, 5b, tuned with the output stray capacitance 9 to a multiple, e.g. two, of a locally generated oscillator frequency applied at 7, 7<SP>1</SP>, with the input signal applied at 1, 1<SP>1</SP>. Devices 4a, 4b switchable in a push-pull configuration may be Schottky diodes and the inductors 5a, 5b may be closely coupled to reduce the inductive impedance to the oscillator current. To correspond to variations of the oscillator frequency, inductors 5a, 5b may be made variable or a variable capacitor may be coupled via a transformer formed from inductors 5a, 5b and an auxiliary winding. |
