Hay Dan,
Why are you miffed? I thought Barney was fairly circumspect in
telling you yer wrong in some cases. Now you are being intentionally
sarcastic. Hardly a way to continue a serious discussion.
When the points open current flow thru the primary winding is NOT
immediately stopped. Current flow decays as a fct of the condenser
charging up as the flow thru the points stops. Remember that the
condenser is at 0 volts until the points open. DC theory goes out the
window and AC takes over, there are TWO LC circuits here; charging the
condenser thru the primary and discharging it thru the secondary. As
soon as primary current decays enough, the field collapses and at some
point the plug fires, allowing electrons to flow up from ground (the
plug), thru the coil secondary to the condenser, dissipating the charge
on the positive plate. When the condenser runs out of charge to
perpetuate the spark the plug quits arcing and it's all over except for
open-circuit ringing.
I've left out the effects of the back EMF, etc. Dust off yer
engineering math and plot the whole cycle across all components.
Publish the plots and I'll be glad to listen respectfully. But for
Pete's sake, there's no reason to get PO'd.
Charley Robinson
`69 B
Look at the current waveform and you'll see that the primary current
declines thru 0 after the plug fires.
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