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MMR40 L2 Winding Diagram

 

MMR40 L2 Winding Diagram

Filed in Kits on Feb.08, 2009

This is how I wound the L2 toroid on my MMR40. I started with the green wire on the right side, as I look at the toroid. After winding 28 turns, I left a loop of an inch or so, and continued winding the turns that show in Red in the diagram. The Red turns are the feedback winding, and the green turns are the main or primary winding.

Note how, once the loop is cut, the Red and Green wires are pretty much straight across from each other. That is how they fall into place onto the PC board. You shouldn't have to cross any wires, they just drop straight into the holes on the PC board.

It doesn't look like it would make any difference if you turned the toroid 180 degrees, as the Feedback wires would still drop straight into the Feedback holes, and the main windings would still drop into the main holes. And since the main and Feedback windings would still be in phase, due to being wound in the same direction on the core, I would expect it to still work. But I haven't tried it both ways, so keep that in mind.

L2 Winding and Mounting Diagram

 

Migrated Comments:

One Response to “MMR40 L2 Winding Diagram”

  1. Bob Says:
    September 12th, 2014 at 3:15 pm

    Thanks for your illustration, was having problem getting PTO to oscillate. Followed your directions, and bingo it worked, Thanks
    NU9DE

 

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