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Re: Ignition coil measurements
> Original Poster: "James" <elgersmad@email.msn.com>
>
>
> >Original Poster: Scott Stephens <Scott2@mediaone.net>
> >
> >I measured an ignition coil and found the following:
> >
> >Core in:
> >primary:
> >L=6mH R=1.6 ohms Q=20 (tested with .1uF @ 3.8 KHz, sharp response)
> >step up ratio=86 (measured with 600 Hz signal)
> >
> >2ndary:
> >L=67H R=8K ohms Q=3 (tested with .1uF cap @ 65 Hz 3dB BW; sharp lower break
> >point, upper response rolls off more gradualy)
> >
> >K= 0.81 which I derived from (correctly? seems .3 too high for solenoid)
> >Step-Up Ratio Measured (86) / SquareRoot [L-2ndry (67H)/L-pri (.006H)]
>
> It's in a tin can, and that changes the magnetic ciruit alot, because
> it's a perfect closed loop, and they use alloy wire which is partly
> ferro-magnetic. You could easily check that with a magnet.
The ones I've seen here are in aluminium. That might explain the
lousy Q. Shorted turn and all that.
?
Malcolm
<snip>