I once had a clock which I found when someone was throwing it away. It ran on a set of (2) "D" cells in series. It was a springwound clock, it would run for about ten minutes per winding. When spring tension got low, a little motor would kick in and wind it back up. A set of batteries would last just over a year.
Finally it died because the motor eventually failed and also the contacts to start the motor got flaky. But it did put in a couple years of good service after I found it. It was not a real precise timekeeper either maybe a minute or two per week or so. Chuck > > >---- Original Message ---- >From: urros...@att.net >To: neonixie-l@googlegroups.com >Subject: Re: [neonixie-l] Re: Transistor ID... >Date: Tue, 28 Apr 2015 07:14:31 -0700 (PDT) > >> >>> >>> This sounds somewhat similar to the now very old, and obsolete >clocks used >>> in automobiles around sixty years ago. They worked like this. A >spring >>> would drive the clock through an escapement. As the spring >unwound, two >>> contacts would make, and a small electromagnet would wind the >spring back >>> up very rapidly. This would happen roughly every five minutes or >so. You >>> could hear it when it happened. Of course no solid state stuff >back then, >>> just brute force mechanics. I took one apart once just to satisfy >my >>> curiosity. Pretty ingenious for the day. Thanks for the fond >memories. >>> Ira. >>> >> >>Actually, they were even more clever than that. To reduce the >>manufacturing precision needed, the tension of the escapement spring >(which >>in concert with the mass of the pendulum wheel determines the "tick" > >>frequency) was adjustable. Furthermore, the adjustment would occur, >by a >>small fixed amount, every time the clock was set. So, if the clock >was >>running slowly, and you reset the time ahead, the spring would be >set a >>little tighter too, so that the clock would then run slightly >faster. >>After a few days of setting the time, it would be perfectly, so to >speak, >>"dialed in". The ultimate accuracy, while never great, could >definitely >>get to be around a minute per week or so. >> >>The only time this screwed up was for daylight savings time >adjustments, >>and even this would correct itself within a day or two of resetting >the >>clock. >> >>(I took one apart too, from the 1970 Cadillac I had in college. At >first I >>didn't understand why some of the linkages seemed so sloppy, then I >>discovered that this was part of the auto-adjustment mechanism.) >>~~ >> >>-- >>You received this message because you are subscribed to the Google >Groups "neonixie-l" group. >>To unsubscribe from this group and stop receiving emails from it, >send an email to neonixie-l+unsubscr...@googlegroups.com. >>To post to this group, send an email to neonixie-l@googlegroups.com. >>To view this discussion on the web, visit >https://groups.google.com/d/msgid/neonixie-l/fd62f3f3-1af0-4d80-829d- >7b963c2df30c%40googlegroups.com. >>For more options, visit https://groups.google.com/d/optout. >> $4.95/mo. National Dialup, Anti-Spam, Anti-Virus, 5mb personal web space. 5x faster dialup for only $9.95/mo. No contracts, No fees, No Kidding! See http://www.All2Easy.net for more details! -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/380-220154228143141548%40all2easy.net. For more options, visit https://groups.google.com/d/optout.