> Hi All,
> This subject is quite interesting, I bought this chainsaw because I need =
one, but
> also because I am very interested on the ignition systems for these small=
 machines.
> On the newer two stroke chainsaws they seem to have just one module which=
 has the
> coil to produce the voltage(magneto), the ignition coil and the pickup co=
il in one.
> This seems feasible but I wander how the timing is done on them. on mine =
it seems
> logical, I have a coil to produce the voltage required for the ignition c=
oil, an
> ignition coil and a pickup coil as separate modules. As I see it the flyw=
heel part
> that has the magnets will pass by the coil which will then generate the v=
oltage
> which will charge a capacitor. then when the same magnets pass by the pic=
kup coil it
> generates enough voltage to trigger a transistor that will discharge the =
cap across
> the primary of the ignition coil, which in turn will produce the HV for t=
he spark on
> the secondary. Is this correct? If so how do you determine proper timing =
and how do
> the new types with the all in one units do the timing for triggering the =
discharge
> of the cap?

I don't believe there is a cap, there is only one coil, and the magnet prod=
uces the high voltage directly. The timing is done by the position of the m=
agnet relative to the coil. The magnetic field and the pole on the coil are=
 shaped to get the rapid change of magnetic field that is required to gener=
ate the high voltage.
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