A workable transformer can be found in an old dial (500 type) telephone. It must be the dial type from the 50’s up that has an actual bell in it. The bell ringer has a coil that will work quite well as a 2 1/3 to 3:1 interstage transformer. I stress the bell assembly, not the network assembly potted in a shell.
These phones are getting hard to find now. I used to pick up old damaged or marked up ones from flea market, phones that they could not sell. I have used them many times in 20’s radios, usually disguised in some sort of shell.
- This reply was modified 1 year ago by Ed Kraushar.