Litz wire is used in long-wave transmitters not on short wave.
de Hans
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>Från: "Dave Bowker" <dbowker@mail.sjv.net>
>Till: <amps@contesting.com>
>Ämne: [AMPS] RE: Litz Wire
>Datum: mån 26 jun 2000 11.32
>
>
>
>
>Litz wire (Litzendraht) is (not) created by simply twisting insulated
>conductor strands together as described in the original posting. The
>insulated strands must be braided, i.e., transposed a manner such that each
>strand occupies all possible positions in the cable to approximately the
>same extent over any given length of the cable. The braiding must be such
>that each strand passes from the center to the outside of the cable at
>regular intervals. This causes the magnetic flux linkages surrounding the
>various individual strands of the cable to be essentially the same for all
>strands over the total length of the cable. By using a large number of very
>fine strands braided correctly, and connected in parallel (only) at the ends
>of the cable, the ratio of the AC resistance to the DC resistance of the
>cable can be made to (approach) unity at the (lower) RF frequencies.
>
>Each strand in the cable must always remain insulated from the other
>strands. Any breakdown of the insulation at any point in the cable destroys
>the effectiveness of the entire cable
>
>The practical limit for use of litz conductors is around 500 kHz, and it is
>NOT effective or useful above approximately 2 MHz. This frequency
>limitation is due to irregularities in the stranding and the capacity
>between individual strands which prevent the ideal conditions to be achieved
>at higher frequencies.
>
>73, Dave, K1FK
>Fort Kent, ME
>
>
>
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