2S57  The Inheritance

This looks like it should have been hanging outside the principal's office in good ol' North Brookfield Elementary School (where I spent many a long afternoon).  The S in the model number indicated its having been designed for an S rotor.  Only a few models would carry an S in the number.  By 1960, the rotor type was dropped from the model number and surviving models renumbered.  This particular model I retrofitted for an H rotor and coil.  All you have to do is (once you tap for screws) is get rid of the posts for the S coil.  The mounting holes for the Fifties, plastic spreader posts are still there on the back plate.