You could. My concerns would be: 1) Noise figure. You will need a low noise amplifier with sufficient gain to overcome the mixer loss. 2) How will you stabilize the frequency of the YIG? You may have better luck with one of the more easily attainable crystal controlled "Brick" oscillators.

Hi all! Could I build a microwave receiver for satellite using a yig, mixer, the appropriate Local oscillator and an SDR dongle for receive of some kind? I do have an IF filter and so forth. Norm n3ykf