03-02-2017, 11:07 AM
John, you will need better than a usual interstage transformer.
The output stage of this radio runs in class AB mode, so you need a driver transformer with a step down ratio and the ability to handle the current of the 42 driver tube. The normal type transformer has a step up ratio and can't carry the high primary plate current of the 42.
Your best bet would be to find a used transformer from another Philco with the same "super class A" output arrangement of the 42 driving push pull 42's.
There is a Hammond driver transformer that can be made to work, but I will have to look it up.
Which winding is open on your transformer?
The output stage of this radio runs in class AB mode, so you need a driver transformer with a step down ratio and the ability to handle the current of the 42 driver tube. The normal type transformer has a step up ratio and can't carry the high primary plate current of the 42.
Your best bet would be to find a used transformer from another Philco with the same "super class A" output arrangement of the 42 driving push pull 42's.
There is a Hammond driver transformer that can be made to work, but I will have to look it up.
Which winding is open on your transformer?
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
