On Tue, 11 Aug 2009 09:26:15 +0200, Philippe
wrote:

brian whatcott a écrit:

I also use the magnets for CDI electronic ignition. no more magnetos,
no more cable for tach, no more copper tube for oil pressure...

By

Not sure if this is what you mean, but a few high energy magnets
spinning on a plate do a great job producing pulses in a few coils
spaced close to the spinning magnets.

I have two simple magnets one north face and the other south face glue
at 0° and 180°.
The sensor is one AH287 and I use two automotive CDI boxes as power
stage for ignition #2.
I use one distributorless box from M&W ignition for #1.

For the electric wiring, I copy the following schematic:
http://www.jodel.com/index.asp?p=potezwiring&engines

My electronics devices are in the the point and distributor ignition
place.
In fact, I built 2 distributorless ignittions like today cars but
still have fix timing.

The wish list is one microcontroler for variable timing.

No way to built a small generator with my magnets. A batteryless
ignition like Jabiru require more start energy than my ignition.


the trick with the magnets is to understand that it is the collapsing
magnetic field that produces the pulse to the spark plug.
if you look at a jabiru magnet there are 3 poles. as the magnet goes
whizzing past the coil the coil sees North-South then suddenly
South-North. the second magnet orientation is designed to accelerate
the collapse of the field through the coil core.
The two outer poles are , say, South and the centre one, say, North or
vice versa.

it is not just magnets on a plate but magnetic pole orientation as
well that makes it work.

Stealth Pilot