This Induction Coil consist of two windings.

Making a Coil No. 1 or No. 12
Coil overall length 2½ inches
Coil former end pieces 1¼ inch square x 3/8 inch thick.
Coil former 1¾ inches inside x ½ inch diameter cardboard tube.
Primary winding 400 turns of 23 SWG (0.6mm) enamelled copper wire - 1 ohm.
Secondary winding 1100 turns of 33 SWG (0.254mm) enamelled copper wire - 25 ohms.
Core - 24 AWG (0.5mm) soft iron wire (All wire can be purchased from




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Last revised: September 28, 2021