Re: Copper Banding?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Kurt Schraner <k.schraner@xxxxxxxxxxx>

Hi Karl, Tyler, all

a slightly more "amateur"-way construction of a ribbon type primary than 
Finn's, is the one I made for a small twin-TC.
My strip primary (ribbon spiral) is made of copper ribbon of 0.55mm 
thickness only (20mm wide). The distance between turns is only 6mm (~1/4"). 
I also don't meet any problems with corona/arcovers, when feeding 33nF 
primary cap with up to 1300W from a 15/60 NST. A pic may be seen at:

http://home.tiscalinet.ch/m.schraner/FlatPrim_1555.jpg

The view is from the bottom side (...when later buildt into the TC). In 
front of the coil are 6 of the really flat taps, developped for this 
primary, mounted on a piece of ribbon for demonstration.

Remember, if calculating the inductance of those primaries, the inductance 
is _less_ than one made of wire/tubing conductors, and calculated by the 
usual wheeler-formula. Metal ribbon type spiral primary inductance 
calculation is available, in form of a zipped Excel, at:

http://home.datacomm.ch/k.schraner/FlatRibbonCoil.zip  (~57kB)

Best regards,
              Kurt Schraner