If you cannot buy Litz cloth easily or cheaply, don't bother waving it by hand - it's just too much work. You can get away with winding several layers of very thin wire (or cheap frayable Litz wire consisting of many thin enameled wires) on some kind of a flexible hose, that is not a part of the system, but has the diameter >= to O.D. of the toroidal winding's crossection. You can wind it using a motorized drill with a stiff rod inside the hose *, because it will easily have 10 thousand turns. After winding it, bend the hose into the circle of the same average diameter as the toroidal coil ...thus creating another toroidal coil that would cover it. Make sure you cannot see the hose through the wires (IOW: the hose is completely covered with wires after bending) - this consideration determines how many layers you should wind on the hose. Varnish the winding on the bent hose to fix its shape. After the varnish cures, cut the winding in half circumferentially, using a knife or "dremel" micro saw, so you obtain two separate concave circles (a top one and a bottom one). Don't fray the edges of the cut, too much. Remove the hose. It will be easy to separate because the two halves of winding will not hug it closely anymore. Coat with solder one circular edge of on top winding half, and the circular edge of the bottom winding half. Do not coat the edges deeply, only the very ends of the wires. Solder the two halves together with a circumferential solder bridge over the RX toroidal coil (insulating kapton tape between them). Do not complete the bridge all the way around - you can't do it anyway because you have the water tube inlet in the way. In other project you would go only 359ยบ around and leave a small gap, or make a small circumferential overlap (better). * Here is a calculation how long it would take to wind the thin wire on a hose using a motorized drill at 300rpm.
« Last Edit: 2020-10-17, 01:18:39 by verpies »
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