Original poster: "Kurt Schraner" <k.schraner@xxxxxxxxxxx> Tesla list wrote:
Original poster: "David Thomson" <dwt@xxxxxxxxxxxx>
<big snip>
http://www.tesla-coil-builder.com/FlatSpiralSolenoidCombo.htm When it comes to winding flat spirals with ribbon wire, there is no advantage from the extra self-capacitance because the flat wire acts like several coils wound in parallel, thus the inductance is decreased accordingly. Calculating the frequency of the flat spiral using the Wheeler inductance formula for flat spirals made from round wire works the same for flat spirals made from ribbon wire. Dave
Maybe I'm splitting hairs, but I have to disagree about the last sentence, of Wheeler formula application for ribbon wire flat spirals. Please see my 2004 TCML posting:
http://www.pupman.com/listarchives/2004/October/msg00018.html especially the 2 graphs: http://home.tiscalinet.ch/m.schraner/Lstrip_Wheeler.gif http://home.tiscalinet.ch/m.schraner/Lstrip_NBS.gifTo use the right calculation method can be crucial, when designing a ribbon type flat spiral primary: the too high L prediction of Wheeler may lead to a too small primary construction.
Kurt