High frequency amplifier.

摘要

The invention relates to a high frequency amplifier comprising two input transistors (T1, T2) forming a differential amplifier stage with an impedance variable by a dc control current interposed between the common terminals thereof to vary the amplification factor. The variable impedance is formed by a diode bridge (31) whose ac terminals (33, 34) are connected to the common terminals of the input transistors (T1, T2) and whose dc terminals (30, 32) are connected to a circuit arrangement for feeding the dc control current to the diode bridge (31).