I understand that T magneto's produce AC current.
When I rebuilt mine 6 yrs ago I borrowed a magnet re energizer from a fellow club member. After assembly I ran the engine, if memory serves correct I believe the mag put out 35 volts AC. Which I was told was within spec. Here I am 6 yrs later finally getting a chance to finish the rest of the car, 26 Tudor.
Trouble is I can't recall how the T converts ac current to DC as it doesn't have a rectifier?
Or maybe it doesn't??
The current from the battery will be DC or course,...so does the magneto use AC current to supply the ignition circuit, which can also operate on DC current from the battery / generator. How about the headlights, can the magneto supply the lights without having a 12 volt battery??
The stock Model T uses the AC current as AC current. The coils are happy with AC. Running them on battery DC is OK, but not as good as magneto AC.
If you want to use your magneto to recharge your battery, go to FunProjects and look at their kit to do just that.
The coils don't care AC or DC and depends on the position of the switch. Yes the bulbs will could work on both also but in your case would operate from the battery which is how it would be wired. AC is only used on your 26 for the coils when switched to magneto. The starter, lights and horn operated on DC which is supplied by the battery and generator. Unless of course you have a non starter car then the lights, ignition and horn would be supplied by the mag.