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Re: Spaced Coil measurements - Addendum.



Hi all,  
        I forgot to include the wirelength stuff:
        
>         As promised, here are the measurements (and they do contain a 
> surprise):
> 
> The Coil:   Hs = 31.5",  Ds = 12.3",  Ns = 38 turns  Dwire = 0.8mm
>             Winding pitch = 1.2 TPI,  former = thinwall PVC tubing

<snip> 
Actual wirelength = 37.9m  c/(4*wirelength) = 1.98MHz   
As usual, a terminal has to be added to bring the frequency down if 
the 1/4 wavelength is to be made to reflect the physical wirelength
as the bare coil resonated at 2.9MHz. No major surprise there for the 
lumped scenario.

Also:

> - Suppose Wheeler is correct. Then Medhurst fails to give the 
> correct figure for Cself (if this were true, reading #1 suggests 
> Cself = 20.4pF, reading #4 suggests Cself = 78pF). This contradicts 

badly *if one takes a lumped view of things*.

Malcolm