I have now checked the bias and to my great surprice there is no drain current!
I measure 0,5mV over each primary, the DC resistance of the primaries is kind of hard for me to measure because it is so low but we can do an estimation:
Now I really wish you had LaTex...
Anyway, here is the estimation:
Lp (poloidal circumference i.e the length of one turn)~4cm
Np (primary number of turns): 90
Lw (length of wire)~90*4cm=360cm=3,6m
rho (resistivity of copper)~1,67E-8
Dw (diameter of wire): 0,7mm
Aw (area of wire): pi/4(Dw)^2=0,38mm^2=0,38E-6m^2
Resistance=rho*Lw/Aw=0,16 Ohm
Drain current is thus around 0,5mV/0,16=3,16mA~3mA
To me, this is Class B.
Best regards, Roger