fc 75 perfluoro 2 butyl tetrahydrofurane fc 87 means a specific 3m product of fluorinert with a boiling point of about 30 u00b0 c this product contains perfluorocarbons comprising c 5 c 18 litz wire is a shortened form of litzendraht wire which is a bundle of multiple insulated and appropriately positioned strands that has lower ac resistance than a single strand of the same cross sectional area this is due to the reduction of the skin effect i e the current of an ac signal doesn 39 t penetrate all the way into a conductor but is limited by the mutual coupling between the strands high frequency currents are known to flow substantially on the surface resulting from the u201c skin u201d effect thus a single thick conductor flowing a high frequency current results in much of the wire not being used as the current flows only on the skin or outermost surface the limitation of mutual coupling is reduced by appropriately positioning or weaving the strands so that each individual strand occupies every possible position in the bundle periodically along the length of the bundle the positioning or weaving equalizes flux linkages and hence reactances causing the current to divide more uniformly between strands referring more specifically to the drawings for illustrative purposes the present invention is embodied in the apparatus generally shown in fig1 a through fig4 it will be appreciated that the apparatus may vary as to configuration and as to details of the parts and that the method may vary as to the specific steps and sequence.