I was looking for my copy of the manual (found the fence manual and the riser block instructions)...but I did find a copy on the internet.

PDF of the manual
https://uwm.edu/psychology/wp-conten...-JWBS-14CS.pdf

It appears that the motor behind version is an earlier version of the JWBS-14OS (contemporaneous with my 14CS) It looks like the 14OS was reconfigured sometime on or before 2011.

John