MRF9120

[VK4DCM]

Hi I got a 100w 2m amp from china this week and built it as per instructions I could set the bias OK without the FET in but now I have the FET in the bias is only 1.5 volts max and it doesen't draw any current. The dc resistance of the gate is 280 ohms and thats whey only 1.5 bias there is 470 ohm series to the gate from zener 5.2 on zenner.
I think the FET is crook Has anyone got a MRF9120 they can measure the gate DC resistance I would have thought It would be very hi resistance.
Looks like a fight with the *****man who sold it to me if it is.
Thanks