| September/October 1976

Model 'T' Ford

7197 Mississippi Street, Merrilluille, Indiana 46410.

Some of your readers are undoubtedly using Model 'T' Ford coils for their gas engines. The intent of the table below is to show voltage and FREQUENCY change with Ford magneto speed.

You will note that the frequency is independent of any deviation in the load on the magneto, but is a direct linear function of the revolutions per minute of the magneto.

This leads up to statement that the impedance of the 'T' coil is increased as the frequency increases. This is quite necessary because if the frequency stayed low, while the voltage rose, the coil would be subjected to over-current with possible burn-out or at least shortened vibrating contact life. Now; if you put pure D.C. into the coil it means that a lower voltage may be used.

This was taken into account by Henry's

excellent engineers as evidenced by the fact that they designed it to operate on a 6-volt battery when not switched onto the magneto.