How to run an electro mechanical quartz clock on a 3 cell damp salt battery ?<br /><br />I have seen various LCD clocks and calculators but not the humble 1.5 Volts quartz clock being run from a home made battery.<br /><br />I tried the lemon battery cell as well, but it required about 6 lemons and the clock stopped running after about 20 seconds.<br />For the salt battery I only need 3 cells.<br />How does it work ?<br />The trick here is to connect a capacitor in parrallel with the battery and clock to make it work.<br /><br />It appears that the clock needs a buffered supply. When the second hand moves the stepper motor in the clock creates a small power surge which the capacitor provides. <br />These home made batteries have only small current carrying capacity of about 1 milli Ampère. The clock motor briefly needs more, even the multimeter doesn't show it and shows a 0.4 mA value.<br /><br />Materials needed:<br /><br />Three old 35 mm film containers<br />Kitchen salt<br />Three strands of 2.5 mm² wire<br />Three galvanised woodscrews<br />A bit of small gauge wire to connect the cells, or use some alligator clips and leads<br />A quartz clock with no battery<br /><br />At the moment I am doing a duration test and will keep you posted with the results.<br />Start 28 June 2009 at about 20:30 hrs.<br /><br />UPDATE ! 01 July 09 well the cklock ran for 12 hours and stopped at 0900 hrs the next morning.<br />The galv. screw had corroded and by wiggleing it a bit the clock started again. and stopped a few minutes later.<br /><br />Findings: as experiment to prove it works fine.<br />For accurate time keeping, just get a normal one dollar 1.5 Volts battery, which will at least last 1 year.
