[Elecraft] Optimal Coil Dimensions - now building it

[Don Wilhelm]

Lee,

For large diameter coils, I usually use PVC for the coil form - easy enough
to wind, and if one wants to wind with bare wire, of course it must be
spaced so one turn does not touch another, so I usually use another wire as
a spacer (which is unwound afterwards).

I have heard that 'square' coils (length = diameter) produced the best Q,
but never did any research on it.  From David's differentiated equations it
is obvious that this is incorrect and the best coils will have the diameter
twice as large as the length.  I will have to find some larger PVC <G>.

73,
Don W3FPR

----- Original Message ----- 

> I cannot believe this.  I have been researching this very thing on the net
for the last week and playing with the equations on an Excel spreadsheet.  I
would like to do some work with tuners, but the dog-on coils are to
expensive.  I want to make the coil and the capacitor from scratch.  So, I
have been playing around with the equations for the last week.  I've also
research liturature about making homebrew coils and have found some very
interesting articles.  I am also researching homebrew electroplating which
seems to be be quite easy to do.  I want to try some tin plating and some
silver plating.  I am most facinated with the fabrication process.
>