That makes sense for a simple mechanical solution, but given the presence of the microcontroller and quite likely a stepper motor I wouldn't have thought that a reverse gearing mechanism would be required.
Howdy, Retroplayer; That threaded rod idea is one I've also been contemplating. Using your illustration labels with C being the output gear, A the idler, and B the driven gear, would you use the threaded rod as the axle for A, or B? The "hooks" are currently made from 18 gauge stainless wire, hardened by heating over a gas range, and quenched in water; I'll try 14 ga. or 16 ga. next, but it would be easy enough to add a loop or two to extend below the present rod to a threaded rod.Your nuts...where might I find those, and by what name? I haven't had any luck with locating them, but they sound perfect. Since I don't want for either the steel rod the steel rod, nor the threaded rod to move due to the hooks that connect them, I'm thinking of adding a 4th gear to the array. It will be below, and between A & B, and if I go this direction, the threaded rod will be it's axle, as well as the pivot point for A & B.I haven't worked out yet what to make the trip levers from, nor how throwing the lever will move the bar that connects A & B. One step at a time. I appreciate the exchange of ideas. My thanks to both of you!