Re: H/D ratio

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Mike <megavolts61-at-yahoo-dot-com> 

 >
 >Hi Luke,
   >   Don't confuse "maximum inductance" with "best size". Actually, in
 >a solenoid coil, the maximum inductance for a given length and diameter
 >of wire occurs at h=0.9r. IIRC a paper on maximizing inductance was posted
 >to the list in April 2002. In such a design, a 20-inch diameter coil would
 >be .only 9 inches high!
<snip>

On the other hand, a 20 foot diameter coil would be nine feet tall and 
would not have such a problems.  For maggies, I think the short/fat coil 
may have some benefits for the primary/secondary portion as well.
Mike