Hello all...A good suggestion...Many of us restore the early battery Atwater Kent sets only to find that the small transformers (in the metal cans) are bad..Buying new replacements can be costly..Try this: In many of the old phones with a ringer bell they have a small transformer that is close in ratings to the A.K. transformers and fit perfectly into the old cans once you cleaned the tar out of them...I find old telephones at second hand stores..snatch them up and give it a try!!!

To clarify, this is the coil on the bell assembly, not the network that is potted in a plastic case.

Ed.