Thursday, December 30, 2021

DBM transformers

The progression of DBM transformers:

The top one is wound on the type core The Chief designer and I used in the original 40/80 receiver. He wound it himself!

The middle one was the next one in the progression. Designer In Training wound it for him. He bragged she had excellent vision.  Good hand eye coordination too!

The bottom one I wound today. I used an eye piece and stumbled through it. For reference the wire is #34.

Two a day is about all I want to wind. Anywho time to build some DBM's. Our previous test told us the smaller ones performed better. The new one should be spectacular????


  1. Are those the binocular cores?
    Yes! Very fiddly but worked reasonably well.

    I see those look from the photograph like they have four wires emerging, are they really for a DBM?


  2. I folded one wire in half and made a twist to be the center tap. It is just a stub so would be hard to see in the picture.