Mallory tech answer to coil/ballast ?

[B_man_Al]

BillM … thanks for the link to the coil site. Well I guess I got to eat some crow here. Didn't know that coils designed to work without a ballast resistor, have them built in! Makes sense though, to allow the primary current to increase at higher speed where the dwell time is reduced. The reduced dwell time (points closed) allows the ballast resistor to cool, thereby reducing its resistance and allowing an increase in the primary current.
Never too old to learn!