RF transformer impedance matching problem for fet mixer

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Joined Feb 7, 2018

I am designing a dual gate mosfet mixer to drive a 50 ohm load. Without the transformer the mixer has a gain of 3, but when I add the transformer and a 50 ohm load the gain is dropped to .5. Also with the transformer the signal is centered around 0 volts, which negates my biasing. I believe I used the correct formula when designing the transformer, Np/Ns = sqrt(Zp/Zs) and I got a turns ratio of 11:2. L values calculated using FT 37-43 core. Attached is the ltspice asc file as well as the mosfet asy and sub files. Also attached are pics of the schematic and simulation results taken across the 50 ohm load.