[GreenKeys] 14-15-19 Etc. motor

[Jim Haynes]

One of the gear set charts I have shows 25 and 50 Hz sync motors - and
those use the same gear sets.  Which says that the 50 Hz motor is four
pole, 1500 RPM and the 25 Hz motor is two pole, 1500 RPM.

One of the curiosities of all this is that the speed governed motors for
Model 15 and friends ran at 2100 rpm, hence requiring different gears from
the sync motors.  Whereas in Model 28 all the motors run at 3600 RPM so
sync and governed motors use the same gear sets.