[AVSorrell]

Hi Group:
I have an open primary on my audio interstage transformer - Philco part # 32-7865N.  The secondaries test fine. I am checking with Heybour to see what the cost would be to have one recreated as Gary does not have one on hand at PTOP. while I am waiting on heybour, I thought I would take a shot at Ron's modification B to the audio interstage transformer when the primary is bad. Below is my sketch with Mondial's corrections noted above (I deleted the original picture he references since it was not accurate):

   

I have also been talking with Gary at PTOP. I mentioned I was planning to do mod B and he didn't think that was the best route. Here is what he had to say:

"Not sure if that is the best way as it is a single plate to push-pull grid DRIVER circuit and not just a plain interstage audio coupling circuit." Gary suggests a DRIVER type transformer and says the spec's are not too critical on type if I am just trying to get it working.  I would like it to work the best it can given i don't have a spare audio interstage transformer (the primary was open on the parts set audio inter. transformer I have too).

What do you guys thinks?  Thanks for your help  - it is really appreciated! -- Andy