Hi Brooke, I've adjusted the watch as best I can within the limitations of the trimmer. The waveform was drifting 10 microseconds (slow) in about 20 seconds and so this should come out to 1 second in 23 days.
I have now set the watch accurately and will follow it's progress. I plan to see how long it takes to be a second out and then re-open the cover and re-check the wave form. >From that I should be able to work out the relationship between the measured frequency and actual watch accuracy. Watch (*cough cough*) this space. :-) Jim P.S. I'm so looking forward to being able to have a genuine atomic watch on my wrist. Surely it can't be too far away... On 16 December 2010 06:03, Brooke Clarke <[email protected]> wrote: > Hi Jim: > > It may not be a good idea to adjust the watch so that the frequency is spot > on at the time the adjustment is made. > A better idea may be to wear the watch for a week and note the fractional > time error then adjust the frequency so the offset matches the error. > > Have Fun, > > Brooke Clarke > http://www.PRC68.com > > > Jim Palfreyman wrote: > >> Fellow time-nuts. >> >> Over in another part of the internet is a group of people who love their >> Casio G-Shock watches. These digital watches have been around for decades >> and are built very well. >> >> The one I own is an "atomic" and solar model (i.e. no battery >> replacement). >> However being in Tasmania, I cannot receive the low frequency time >> signals. >> When I first received the watch it's accuracy was excellent. Under 10 >> seconds a year. I even posted on here about it. Since then though it has >> drifted somewhat. >> >> After a ton of internet searching on how to open the case and how to >> adjust >> these watches (this is non trivial as the models are all very different >> and >> no instructions existed for this model - the GW-810D) I have finally >> cracked >> it. >> >> Interestingly, the module has a pad that gives off a stepped square wave >> at >> 32768/48 Hz. So with well calibrated equipment (which we all have of >> course) >> it is trivial to adjust the trimmer to put the watch back to decent >> accuracy. Using the smallest adjustment of the trimmer that I could muster >> I >> could get it down to about 0.5 in 10^6 or 1 second in around 20 days. Not >> as >> good as when I got it - but I was probably just lucky. >> >> Over in mygshock.com they struggle with this sort of timing stuff - >> whereas >> my big deal was opening the case! >> >> Just posting in this in case anyone here is interesting in adjusting their >> G-Shock. >> >> Jim >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> >> > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
