Hi. I need an audio interstage transformer that drives two type 47 output tubes in an RCA R11 chassis. The center-tap on the secondary of mine is open. The RCA part number is 7271. If anyone knows of a replacement part, please let me know.
Thanks.

A pic would help. I probably have something similar.
If the coil has continuity across the ends:
1. You have a good coil with a broken wire or bad solder joint from the center of it. Most likely at the point where the small xformer wires connect to a larger interconnect wire or maybe at the terminal solder joint.
2. Give the resistance reading across the coil. That would make it easier to ID a replacement.
3. This one works good enough in other sets.
http://www.hammondmfg.com/radiola1.htm

I checked the coil resistance. The primary measured 2.5k ohms and the secondary measured 4k.
Does anyone think it likely one of the replacements from AES would work?
In this circuit, a type 27 drives two type 47's.

Thanks.

FYI, Hammond 118944 is 4000T to 6000T/6000T. It will give a 1/2.25 impedance ratio.

Edit - it sounds like yours has a good secondary winding and the connection to the center tap terminal is broken. This is a good candidate for explorative surgery. You may well be able to fix it.

It's potted in tar inside of a can and would be a bit messy.

Thanks for the info.

Dave

What about the PT-156 under Hammond ?

Freeze the coil and carefully chip the potting out around the center tap wire.