Re: 120AC,Dimmer, 12vauto coil,Cap

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Ed Phillips <evp@xxxxxxxxxxx>

Hi John,

To answer your question, the 120ac input,dimmer
switch,12v auto coil and cap will produce AC current
if you use AC input and it will produce DC current if
you use a DC input.

Bobby,"

	First part is correct but the second is wrong.  Running the circuit on
DC will produce nothing because of the capacitor in series.

	The output of the coil will be AC for sure, but typically there will be
a large peak of one polarity followed by a shorter, longer peak of the
other.  In this sense it is similar to the standard spark coil.  In the
case of the light dimmer circuit alternate firings will produce outputs
of alternating polarity.

	I usually use Triac circuits excited by DC (NOT the same as the light
dimmer arrangement) and, at least to a gas discharge tube, the output
appears to be more or less unipolar although of course it really isn't.
The output can be rectified with a suitably-spaced spark gap (breaks
down only on the higher peak) and stored in a capacitor.

	Of course, with any inductive device the AVERAGE output voltage must be
zero so without a rectifier there can be no DC flowing.

Ed

Ed