You need a round ferrite former.
I got mine from an old computer. They are usually used as RF
supressors on the switch wires.
The dimensions of mine was;
15mm Inner diameter
27mm Outer diameter
12mm Height
Start by winding L3, 450 turns of 0,1mm
You can fix each layer with some epoxy, but i did not, and it
was OK anyway. |
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Wind on L2, 10 turns of 0,1mm
Please note that all 3 layers must be wound in the same
direction.
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Finally, wind on L1, 20 turns of
0,5mm
When the coil is tested, you should put on some epoxy. |
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