On Sat, 14 Feb 2004, Chris Lusby Taylor wrote: > I recently bought a 24 hour quartz movement for a heliostat project. > It took months to arrrive, cost ?35 and is of no better quality than the 12 > hour movements sold for ?1.99 by Argos as alarm clocks. So, I'm now > converting a ?1.99 movement by butchering one of its wheels. Actually, I've > made it go at a quarter speed, so it becomes a 48 hour movement. After > aligning its axis with the poles, a mirror attached to the hour hand then > reflects a spot of light in the same direction all day long. Over a year it > traces a figure-of-eight on a wall. > > Regards > Chris Lusby Taylor > 51.4N, 1.3W
Great idea! An anlemmatic calendar... Are these the typical, small, plastic quartz clock movements? What did you do to "butcher" the wheels? Too bad it isn't particulary practical to modify the electronics; adding two more divider stages would accomplish the same speed reduction, but everything is so integrated and encapsulated. I assume there is one chip (probably appears as an epoxy "blob"), a crystal can, and a tiny pulse motor. It takes little more, now. How did you arrange the clock movement and mirror, physically? Dave 37.277N 121.966W -
