Bill, Indeed undoing the four screws is all that's needed. However on some models those screws are covered by various plastic bits which are quite confusing to remove. (Unless you are a gshock-nut!)
Jim On Wednesday, 15 December 2010, Bill Hawkins <b...@iaxs.net> wrote: > Jim, > > I have such a watch, purchased in Singapore in Oct 2009. It is > solar, but it has no radio connection. It is water-resistant > to 20 atmospheres (bar). I don't wear it, but I keep it by a > southern window. > > The back cover appears to be held on by four screws. I've not > tried to open it. It's off by two hours and 91 seconds, over > a year. It's possible that I didn't make the final time zone > adjustment when I got back to Minnesota. > > What was the problem with getting the back off? > > Bill Hawkins > > > -----Original Message----- > From: Jim Palfreyman > Sent: Tuesday, December 14, 2010 10:17 PM > To: Discussion of precise time and frequency measurement > Subject: [time-nuts] Adjusting accuracy of a Casio G-Shock watch > > 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 -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
