[morzh]

A centertapped transformer might be ether for P-P 47 or 45. Or it can be for Philco 20.

In either case it will work for SE if only ends of the primary are used (and I heard people did exactly that) but at least in theory it is not an adequate thing to do as a P-P xfmr usually has smaller core as it is not afraid of saturation. A SE xfmr usually is a larger one, to deal with DC saturation. So the P-P one might get somewhat saturated which might distort the output and lose the power, plus your primary inductance and all will be screwed up.