Blade elevation mechanisms and anti-backdrive mechanisms for table saws

A table saw comprising:

• a table defining a work surface;
• a substantially planar, circular blade configured to extend at least partially above the work surface;
• a blade support structure configured to support the blade;
• a motor to spin the blade;
• and
• an elevation system to change the elevation of the blade and blade support structure relative to the work surface, where the elevation system includes a handwheel adapted to be turned by a user to change the elevation of the blade and blade support structure relative to the work surface;
• and
• a cable spool operatively associated with the handwheel to turn as the handwheel turns;
• and
• a cable assembly comprising a first cable section with two ends and a second cable section with two ends, where one end of each section is operatively connected to the cable spool and the other end of each section is operatively connected to the blade support structure, and where the cable sections wind and unwind on the cable spool as the cable spool turns;
• where one of the first or second cable sections winds onto the cable spool and the other of the first or second cable sections unwinds off of the cable spool as the cable spool turns;
• and
• where the winding and unwinding of either the first or second cable section raises or lowers the blade.