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Re: WIRE CHART



RWW wrote ....

> I'd like to jump in here and put in  my 2 cents worth.  This
> actually costs me about 2.8 cents in my quaint Canadian money.  I
> think I understand t he physical geometry of the coil winding
> technique which Brad Alheim is attempting to describe, and I'd like
> to suggest that where it's merit might best be used to advantage,
> that is to say as Brad poin ts out, it has reduced interturn
> capacitance, might be a good way to wind a high performance
> SECONDARY coil! This is where interturn capacitance is really a
> problem to performance.

I think this method of winding has been referred to as a "spider-web".
I have seen a sketch (presumably from a photo) of Tesla sitting beside
a huge winding of this sort. It used to be quite commonly used in
"portable" valve radios as a low-C antenna. I can't remember whether
the one I saw was tuned as the first RF tuned circuit but its low
capacitance would lend it well to being tuned by a standard variable
capacitor.

Malcolm