toroids

Toroids

Selecting, Winding, Testing, Mounting, etc.

While most toroids used by ham radio operators have powdered ferrite or iron tape cores, it is possible to wind toroidal inductors on plastic disks, wooden beads, and so on. These "air-core" toroids may require more turns than their metallic core cousins, but they still work much the same way and exhibit some of the same characteristics.

Here is a simple wire twister to help in making bifilar, trifilar, quadrafilar, etc. toroid windings:

Wire Lengths for Winding Toroids

IPT = Inches Per Turn