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Re: Wire Guage Sizes (for Q)
Subject: Re: Wire Guage Sizes (for Q)
Date: Wed, 28 May 1997 18:46:35 -0400 (EDT)
From: richard hull <rhull-at-richmond.infi-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
>
>There is one bottom-line relationship between wire guage
>and secondary size, and that is Q.
>
>The secondary coil will transfer most of its energy to the
>arc in less than 10 cycles, when properly designed and
>loaded. Therefore, as a rule of thumb, the unloaded Q of
>the secondary should be about 100, since any increase
>in Q beyond this point can yield only single-digit percent
>improvements in the efficiency, and cost seems to go up
>as the square of Q.
>
>Given that Q = 2*pi*F*Lsec/Rsec, and Q = 100,
>
>Then Rsec = 2*pi*F*Lsec/100.
>
>At this point, plug in your favorite equations that relate
>coil size vs. frequency and inductance, and
>wire resistance vs. winding length and skin depth.
>
>-GL
>
>
I would agree wholeheartedly here. Most of our work indicates that a
coil
with a naked 707 bandpass Q of more than 120 is just an exercise in
futility. A coil seems to do its best between a Q of 80-100 anything
below
this and you see a differential (in the toilet), anything much above you
don't see much of anything (no increase). A good heavy loaded Q might
be in
the 40-80 range depending on coil size and other factors. These guarded
generalizations are from measurements and real multiple working system
analysis and not maff coagulation.
Richard Hull, TCBOR