Fw: Scope pics...

[Bruce Plecan]

Thanks Shannen
If ya all (who are still interested), look at this, maybe we can get
somewhere.

 http://www.aeswave.com/framedcatalog/product_0112sec.htm#accessories

Starting at the left edge:

Is a *12* volt signal,  then we have the points close signal (note there are
coil condenser oscillations {ie A/C}), As the coil saturates you see the
voltage build, then the point open signal a huge vertical spike, note that
the are some *notches* *steps* as the voltage is at or near the max voltage,
these are the coil oscillations of the *ringing of the collapsing* fields,
*typically* this spike is around 25Kv, and is when the ionization is forming
between the electrodes, finally there is an arc over, and the *firing line*
reflects that with a horizontial segment (again typ. 12 Kv), that can vary
(at idle) from .7 to 1.8 msec. that is the time where there is an
established arc.  Once there is no longer enough *ions* between the
electrodes, the voltage is no longer high enough to maintain an arc and the
arc stops, and there is the large drop to 0 and even slightly less.   But,
there is the current that was shut off still ringing in the system remember
the points are still open so there is still energy to disipate,  we ran out
of ions for a 12Kv path so we have 11.5Kv (about) that will have to
disipate, and then we have the large coil condneser oscillations.  Then we
go off screen, and would again begin at the l/h border, and begin the cycle
all over again.
   Other then at the + side of the coil everything else is voltages from the
collapsing fields weither charging or discharging,  the coil, A/C

Take a transformer,
   Put a meter across  the secondary posts,
   Apply power to the primary,  secondary pegs for an instant, then goes 0,
with the primary is still on, remove primary voltage another spike, again
output goes to 0.   Transformers don't work on a strickly DC component,
That's the best I can do.
Slice it anyway you want but that is the only circumstance that explains all
the conditions for a Waste spark.   IE one plug, can fire reguardless of the
is going on with the other.

Take a convention autotransformer with a point open signal the one side of
the secondary is only to 12+ thru the primary.   Since one side of the
secondary is open to ground I guess the plug never fires.

You check for spark with a grounded tester so that there is some control of
spark energy.
Opening both sides of a secondary side of ignition coil will force then
spark energy to disipate somewhere, and that is what ever is the path of
least resistance.   If the points are open the A/C will just ride along the
12+ supply side just fine.   Well til the capacidance (?) of the battery
*absorbs* it...

HTH
Bruce


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