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Tapping close wound coils

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Putting a tap on a inductor coil whose turns are spaced rather closely together can pose somewhat of a problem. For example, a No. 20 wire will not pass between the turns of a coil of No. 24 wire wound 32 turns per inch. A solution is to flatten the end of the wire used for making the tap. This can be done by putting the wire on a hard flat surface and pounding it flat with a hammer. The wire can easily be flattened to a thickness of a few thousandths of an inch so that it can be wrapped around a coil without shorting adjacent turns. The wire can be annealed to its original pliability by momentarily heating it red hot over a flame and allowing it to cool slowly. After cleaning the wire with steel wool it can be soldered in place easily; small strips of aluminum foil alongside the tap will keep the solder from running to adjacent turns.

Leo B. Weiner, W3LOS.