Interesting Find: Auto DST in GW-3000B

6860 Views 22 Replies 13 Participants Last post by mikenbetts, Apr 24, 2013

bluebunny63

Discussion Starter · Aug 13, 2011

Found something interesting in my new GW-3000B (Module 5121): at least in the USA, it sets Daylight Savings Time (DST) to "on" when it synchs within the four continental USA time zones.

Here's the situation: I'm in Arizona, where it's MST year-round (except for the Navajos).

1. Set my home city to Denver (DEN).
2. Set DST to off (the indicator says STD, meaning standard time).
3. Returned to normal mode, and everything is kosher.
4. Let the watch synch overnight.
5. Next morning, watch is an hour ahead, and when I display my home time zone, it still shows it as Denver, but with DST "on".
6. Checked the synch indicator, and it says "Y" (Yes, I synched).

So... I figured I made a mistake with the home time zone, so I tried it again. Very carefully following the manual.

Next morning, guess what? Denver is magically set to DST "on" again. Tried this two nights running, with the same results.

Conclusion?
The GW-3000B has an undocumented auto-DST feature. Only thing that I could find supporting this in the manual was this cryptic entry: "As of November 2009, China does not use Daylight Savings Time (DST). If China does go to the Daylight Saving Time system in the future, some functions of this watch may no longer operate correctly." In other words, there is an automatic DST setting for certain time zones, and China is not currently one of them (implying that other zones, namely North America and maybe Europe, are).

I'm posting this for the benefit of others in non-DST locations (AZ, IN), who might otherwise be scratching their heads, thinking that they did something wrong by setting their watch to the correct time zone, overriding DST, and then finding the watch an hour off after a successful synch.

Personally, I'd rather Casio left well enough alone, and allowed an override of DST for every time zone, but there you have it. My fix for the thing, of course, is to simply set my home city to LAX for Summer, and DEN for Winter... oh how I wish they had an AZ zone on their watches.

See less See more

Reactions: 1

1 - 20 of 23 Posts

jmathis

· #2 · Aug 13, 2011

I wonder if the same result would be for Hawaii. Hawaii does not switch to DST, either. Always HST, Hawaii-Aleutian Standard Time (UTC -10 hrs).
I'd definitely be interested in the automatic radio time-reception of the CASIO G-shock all-analog watch when in Hawaii. My Riseman GW-9200 sometimes syncs to the radio time. I'm keen for the Giez GS-1150 or GS-1400, and with your auto-DST report for the GW-3000B, I wonder if the Giez would be plagued by the same auto DST offset whenever it sync'd. I wonder if there is an equivalent UTC -11 hrs zone on the Giez, so to set the watch one hour back, as you do to West Coast time when AZ stays doesn't move to DST? I like the Giez a lot, and I never ever considered this situation. Thanks, bluebunny63, for calling this "feature" to my attention.

sidecross

· #3 · Aug 13, 2011

I have three of these watches and you have to press 'button B' to switch from 'standard' to 'day light savings' when setting 'Home Time'; it is not automatic.

bluebunny63

Discussion Starter · #4 · Aug 14, 2011

sidecross said:
I have three of these watches and you have to press 'button B' to switch from 'standard' to 'day light savings' when setting 'Home Time'; it is not automatic.

Hi Cross,

That's what I did, too. And yet, as I described above, it reset itself to DST on, even though I had set it to off. My only thought is that since I've got Pacific, Central and Eastern set to DST on, the watch assumes that having DST off with Mountain is an error.

It's a bit of mystery to me still.

c double j

· #5 · Aug 14, 2011

i too have found something interesting. In my black/red gx56, if you press adjust, mode, and search all at once it lights up everything that could be readable including rcvd. i know that stands for a received time calibration. whats strange though is that this is not an atomic model because its not a gxw56. anyone reply if you have an answer

Lexxorcist

· #6 · Aug 14, 2011

Sounds like they might be using the same display in the atomic and non atomic versions.

sidecross

· #7 · Aug 14, 2011

bluebunny63 said:
Hi Cross,

That's what I did, too. And yet, as I described above, it reset itself to DST on, even though I had set it to off. My only thought is that since I've got Pacific, Central and Eastern set to DST on, the watch assumes that having DST off with Mountain is an error.

It's a bit of mystery to me still.

I better understand what you wrote.

I set my world time to UTC and I have not experienced what you have.

I have no idea why this might be happening.

sidecross

· #8 · Aug 15, 2011

If anyone finds the cause of this problem, please give us the information.|>

Wally79

· #9 · Aug 15, 2011

sidecross said:
If anyone finds the cause of this problem, please give us the information.|>

The cause is that the watch module follows the time signal's dst information (starting, on, ending, off) WWV (radio station) - Wikipedia, the free encyclopedia

Some watch modules use the time signal dst info and others don't

Reactions: 1

sidecross

· #10 · Aug 15, 2011

Wally79 said:
The cause is that the watch module follows the time signal's dst information (starting, on, ending, off) WWV (radio station) - Wikipedia, the free encyclopedia

Some watch modules use the time signal dst info and others don't

Thank you for this information;I put it in my favorites so I can find it again.|>

bluebunny63

Discussion Starter · #11 · Aug 16, 2011

Thanks Wally - added it to my favs too. Also, thanks for solving the mystery.

fwupow

· #12 · Aug 18, 2011

All I know is that my Solar Atomic G-Shocks have a setting for DST which can be set to "ON/OFF/AUTO" If set to "OFF", it should stay OFF after syncing but I've never tested that out.

chief

· #13 · Mar 26, 2012

I just bought a GW3000-BB1 and live in AZ. I spent hours tinkering and searching for info - and only now stumbled on this thread! :-/ I had reached the same conclusion: Module 5121 auto syncs in North America and sets the DST based on the signal. It seems with this watch there is no way to "turn off" DST, which is a little annoying for folks like me in non-DST time zones. Both my Citizen AT Chrono (H610) & my Casio Waveceptor (4717) provide this capability - meaning they are truly set and forget. I love every other aspect of this watch, but I am disappointed that the designers of this module missed this simple, yet very important capability for an "atomic" timepiece.

AirWatch

· #14 · Mar 26, 2012

If you select a Home City, like DEN, which is on the Auto Receive list, the watch will then always sync to the correct time in that Home City as defined by the transmitter, regardless of your DST setting. The DST setting mostly comes into play when you have difficulty in receiving a signal or when the Auto Receive feature is turned off altogether.

In other words, when Auto Receive is successful it will show the correct time of the chosen Home City. You cannot override this by the DST setting to match the time in your city which is different from the Home City.

Does that make sense? See, if you could be allowed to fool around with the auto-sync like that, then that would jeopardize the whole design idea and integrity of a radio-controlled watch.

chief

· #15 · Mar 26, 2012 (Edited)

AirWatch said:
If you select a Home City, like DEN, which is on the Auto Receive list, the watch will then always sync to the correct time in that Home City as defined by the transmitter, regardless of your DST setting. The DST setting mostly comes into play when you have difficulty in receiving a signal or when the Auto Receive feature is turned off altogether.

In other words, when Auto Receive is successful it will show the correct time of the chosen Home City. You cannot override this by the DST setting to match the time in your city which is different from the Home City.

Does that make sense? See, if you could be allowed to fool around with the auto-sync like that, then that would jeopardize the whole design idea and integrity of a radio-controlled watch.

That surely is one way of looking at this (basically, "it is what it is"). But, it is a perspective that hardly exonerates this watch for being short of capabilities offered by other (older) watches in its same class - by taking control from the user. If this is a new trend in design, I hope is at least a conscious strategy to devalue WWVB-based timepieces in advance of GPS-based ones on the near horizon. Otherwise, I can only consider it a flaw (one I'll be reminded of twice every year I still own it).

madman01

· #16 · Mar 26, 2012

What the watch does must be wrong.

It seems to me like you have discovered an error in the firmware of the watch and it would be worth the while contacting Casio.

The manufacturer has taken into account the fact that there are areas which do not observe DST.

For this reason there are intentionally three possible settings for DST: 1. AUTO (the DST will be driven by whatever the radio signal says), 2. OFF (the DST will be off; and whatever the signal says about DST will be ignored), 3. ON (the DST will be on, and whatever the signal says about DST will be ignored).

If you are sure you set your DST to OFF, but the watch is behaving as if it were AUTO, you should write to Casio as they have a mistake somewhere in their plans.

If you set your timezone "one zone back", this might be a solution for you to display correct time in the main timekeeping mode, but of course will affect the time shown for other time zones in the world time mode

gaijin

· #17 · Mar 27, 2012

madman01 said:
What the watch does must be wrong.

It seems to me like you have discovered an error in the firmware of the watch and it would be worth the while contacting Casio.

The manufacturer has taken into account the fact that there are areas which do not observe DST.

For this reason there are intentionally three possible settings for DST: 1. AUTO (the DST will be driven by whatever the radio signal says), 2. OFF (the DST will be off; and whatever the signal says about DST will be ignored), 3. ON (the DST will be on, and whatever the signal says about DST will be ignored).

If you are sure you set your DST to OFF, but the watch is behaving as if it were AUTO, you should write to Casio as they have a mistake somewhere in their plans.

If you set your timezone "one zone back", this might be a solution for you to display correct time in the main timekeeping mode, but of course will affect the time shown for other time zones in the world time mode

1. There is nothing wrong with the watch. A simple workaround solves the problem.

2. There is no independent setting for DST as you describe for the 5121 module. If one sets the watch for a time zone that receives a signal, DST is ALWAYS set to AUTO. DST can temporarily be set to ON/OFF, but this setting will be overridden when the watch next syncs successfully to conform to the DST info in the time signal.

3. Setting the time zone one zone back will have no effect on world times. In this case, setting the watch to LAX (GMT -8) will display the correct time for Arizona when LAX is on DST (GMT -7). Since the watch thinks it is in LAX and displaying the correct time for LAX, all other world times will also be correctly displayed. The fact that the watch is physically in Arizona (also GMT -7) has no effect on world times.

The only way to turn DST permanently ON or OFF is to set the watch for a time zone that does not receive a signal and set all time/date functions manually. In this case, the watch will not even attempt a sync. If the watch is set to a time zone that receives a signal, it will ALWAYS be overridden by the DST information in the time signal.

HTH

See less See more

Reactions: 1

madman01

· #18 · Mar 28, 2012

Hi gaijin, thanks for your post.

ad 3. I realise now that my brain failed me when I was writing my last post, and that, really, the world time will be all right with this setting.
ad 2. I also realise (what I didn't know before) that there are moduls which do not have the independent DST setting, but still
ad 1. I thing it is wrong, although now I know that it was the intention; as it is about as 'simple' as having to set your watch everytime the time changes -- so people in the areas with no DST are losing the 'time is changing -- you don't have to' factor

although their government wanted them to have the opposit i.e. be the only ones in the area who do not suffer about the time being changed -- a bit paradoxical if you ask me

chief

· #19 · May 11, 2012 (Edited)

gaijin said:
1. There is nothing wrong with the watch. A simple workaround solves the problem.

^ This statement alone tells it all. If there was nothing wrong with the watch, then there wouldn't be a problem that requires a simple workaround!

The watch has a design flaw, whether it was a conscious decision or an oversight, 2% of the U.S. are burdened with a diminished user experience (semi-annual workaround). I suppose when one considers the extra cost it must have meant to have a fifth position (DST Off) for the radio control dial, perhaps the potential loss in sales was not substantial enough to justify including it. And in the case of me - this would be true! I bought the watch. But I am wiser now. Pay attention, Casio: I buy watches. Make any more "atomic" watches without this feature and you can count me out.

Reactions: 1

gaijin

· #20 · May 11, 2012

chief said:
^ This statement alone tells it all. If there was nothing wrong with the watch, then there wouldn't be a problem that requires a simple workaround!

The watch has a design flaw, whether it was a conscious decision or an oversight, 2% of the U.S. are burdened with a diminished user experience (semi-annual workaround). I suppose when one considers the extra cost it must have meant to have a fifth position (DST Off) for the radio control dial, perhaps the potential loss in sales was not substantial enough to justify including it. And in the case of me - this would be true! I bought the watch. But I am wiser now. Pay attention, Casio: I buy watches. Make any more "atomic" watches without this feature and you can count me out.

Sorry. I had not fully realized the severity of the burden this workaround places on the owner.

HTH

1 - 20 of 23 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.