A friend and I are having a discussion on another forum, and I can't figure out if he's right or if I am, so I was hoping that maybe one of you smart guys could straighten me out.
In a "Kettering" points-type ignition, does the condenser (by charging) serve only the purpose of preventing spark at the points, or does it also (by discharging) create a sudden negative voltage spike on the coil primary, and thus amplify the coil's voltage transformation?
If you believe the condenser functions only on its charge cycle, by suppressing spark at the points, and that its discharge is not necessary to the operation of the Kettering system, how do you explain the rather modest turns ratio of an automotive coil? If only a max of battery voltage were ever present on the primary, you would need a higher turns ratio in order to get enough spark from the secondary.
But if you believe that the condenser also functions upon discharge by creating a negative voltage bucking the forward current flow in the coil primary, how do you explain the fact that (I think) such an engine will run with the condenser disconnected?