----- Original Message -----
From: "Radio WC6W" <wc6w@juno.com>
> Wrong.
>
> The turns ratio works just as expected in that application. The
> secondary voltage is equal to the primary voltage multiplied by the turns
> ratio.
Anyone checking a power transformer with a high-current ohmmeter knows this
effect well. When you pull the meter leads, you are lucky of you don't blow
the meter out or get knocked on your rear!
Ford ignition coils, for the high-energy Duraspark system, which essentially
was a solid-state spin-off of a conventional points system, used a 38 or 40
:1 turns ratio ignition coil. Run outside and grab the ignition lead on a
running Ford engine from the 70's through 90's, and see if that feels
anything like 400 volts!
GM used a similar HEI system, with turns ratios in the same general area. As
a matter of fact you can buy a beefy replacement coil at:
http://www.taylorvertex.com/catalogindex/2002TV78.PDF and up the ratio
to 70:1 to get 40kV spark. The HEI ignition applies less than 10v to the
coil primary, and again is a solid state version of a points system.
Your argument about the capacitor argues against your claim voltage only
relates to turns ratio. If the voltage was only 10 volts or so upon release,
you would never have an extended points arc during release. The primary has
a 1:1 ratio with itself, yet the peak voltage can be hundreds of volts.
Flyback transformers, switching supplies, and even tank circuits all go into
this mode whenever applied energy is not removed over an equally long period
of time. The voltage increases until the stored energy is somehow
dissipated.
73 Tom
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