> Actually, I don't think there is such a thing as a coil with an
> 'internal ballast' rather just coils constructed to not require a
> ballast.
Only a matter of semantics. Coils that don't require an external ballast have
enough DC resistance to not need one. Whether the effect is achieved by using a
discrete internal resistor (and somewhere I have a reference that mentions the
internal ballast, chosen to have a high temperature coefficient of resistance)
or by using higher resistance wire in the primary really doesn't matter.
> The external ballast resistor or wire was added (to a modified
> coil design)
Ironically, in many cases it was actually an earlier coil design originally
intended for 6v operation.
Randall
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