[Arran]

Jayce;
Failed power transformers seems to be a fairly common fault in West German sets (I say West German because there are also East German sets out there, at least in Canada). One feature, and perhaps disadvantage on the W German sets is the tapped primary on the power transformer, I have a feeling that many were used on the wrong setting, they should have been set on the 120-125 volt tap, not the 110 volt one, whether this could cause some of the failures I don't know, but insulation breakdown on the H.V secondary is a possibility over time, causing shorted turns, you are also overrunning the tube heaters this way. Running the sets with leaky caps can also do this, and the selenium bridge rectifiers can also short. I think many were like brand Z sets, used a barely adequate transformer with no room for failure, smaller cores equal less copper wire, and less wire costs less money. I think the same motivation was why they used a selenium bridge, no need for a rectifier tube winding, and they could use thinner gauge wire in the tube heater winding instead of opting for a 6X4. The East German tube sets I have encountered used tube rectifiers, which is odd because as Mike and Peter can attest the Soviet radios from that era used selenium ones.
Regards
Arran