Wide dynamic range mixing circuit

Shown is a wide dynamic range mixing circuit . It uses two symmetrical field effect transistors and input and output transformer coupling methods
. The RF signal input end is equipped with three transformers (Ti, T2, T3), which are symmetrically added to the deep electrode of the II field effect transistor, and the local oscillator signal
is simultaneously added to the gate of the field effect transistor . The output stage forms a push-pull type and has a frequency selection function. The frequency selection circuit resonates at the intermediate frequency (20.6 MHz).
    The input transformer turns the single-ended input (50n impedance) into a balanced output (200n impedance). The circuit features high dynamic range, but
the voltage gain is less than 1.