Casio G-Shock time sync radio

Yes, as others have stated this is an old technology. I don&#x27;t really understand why this is not more common in the modern day. it&#x27;s not really that expensive to implement and they did it with analog chips back in the day...<p>Why do we have to set the time on our clock radios or on our microwaves or whatever? Why don&#x27;t they just always use this Tech. I don&#x27;t understand. All you have to do is allow people to store an offset for the time zone, and RTC issues are a thing of the past.

I spend most of the time out of range, but the technology is simple and robust enough that you can use headphones or a phone speaker as a very, very short-range transmitter. You hardly need to sync every day, either. I&#x27;ve had most success with <a href="https:&#x2F;&#x2F;einoko.github.io&#x2F;DCF77.js&#x2F;" rel="nofollow noreferrer">https:&#x2F;&#x2F;einoko.github.io&#x2F;DCF77.js&#x2F;</a>

I wore a G-Shock Wavecepter while serving in the U.S. Marine Corps. I recall that on both of my shipboard deployments (2004 and 2006) I was very excited to have my watch set time automatically. It indicated that I was finally nearing the U.S. East Coast. It helped to be an aircraft mechanic on night crew, as I was usually on the flight deck when it tried to set time.

Related thread with local transmitters of time signal: <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=27769403">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=27769403</a><p><a href="https:&#x2F;&#x2F;github.com&#x2F;hzeller&#x2F;txtempus">https:&#x2F;&#x2F;github.com&#x2F;hzeller&#x2F;txtempus</a> (A DCF77, WWVB, JJY and MSF clock LF-band signal transmitter using the Raspberry Pi)<p>ios and mac app: <a href="https:&#x2F;&#x2F;forum.audiob.us&#x2F;discussion&#x2F;49109&#x2F;pips-a-radio-time-signal-generator-for-ios-mac" rel="nofollow noreferrer">https:&#x2F;&#x2F;forum.audiob.us&#x2F;discussion&#x2F;49109&#x2F;pips-a-radio-time-s...</a><p>(time sync over rf is super cool; I would be super interested if anyone has links to field surveys of time signal availability, potential gaps in coverage, and maps of said data.

Casio are the best watches I&#x27;ve ever owned. Radio sync on a watch is awesome for creating &quot;drop the mic&quot; moments showing how far out the clocks are on a multi-million dollar machine in a datacenter despite how much the big consultancy thinks they are synced to UTP via &quot;atomic clocks&quot;.

If you&#x27;re interested in buying a Casio watch that does this they tend to be called Waveceptor, I&#x27;d recommend looking at one that&#x27;s also solar powered (tough solar).

I inherited one of these Casio Waveceptor watches from my father.<p>It routinely will set itself to a totally random time far into the past&#x2F;future. I&#x27;ve wondered if maybe contemporary wireless devices interfere with the time sync radio. Another possible factor is the watch itself is ~20 years old.

I have an alarm clock with this system (or I think it&#x27;s this, it&#x27;s from Oregon Scientific) and it has this &quot;automatic clock sync&quot; feature.<p>I have it disabled. Once it was set to a random time, and I lost an important meeting because the alarm didn&#x27;t ring at the correct time. The usual time doesn&#x27;t deviate more than a second or so every few years, when I need to change the batteries and set it again so it&#x27;s useless.<p>This automatic feature would be perfect if it acted as a &quot;press this button to setup&quot; or at startup, but the issue is that the messages are sent very sporadically so you either need to wait almost a full day for it to sync (clocks are not always listening, so it needs to coincide the &quot;push&quot; and the &quot;listen&quot;) or set it manually.

Back in school, we learned how basic binary protocols work using DCF77 as an example. We decoded it on a piece of paper. Good old times.

They misspelled Mainflingen, where the German DCF77 transmitter is located, as &quot;Mineflingen&quot;, which is basically spelled phonetically (for English speakers).

My $0.02: Junghans solar radio watch. Analog display, smartphone app. Runs up to 21 months when fully fed. Never buy a battery again.<p><a href="https:&#x2F;&#x2F;www.junghans.de&#x2F;en&#x2F;collection&#x2F;watches&#x2F;junghans-radio-control-solar&#x2F;force-mega-solar&#x2F;18143644?c=553" rel="nofollow noreferrer">https:&#x2F;&#x2F;www.junghans.de&#x2F;en&#x2F;collection&#x2F;watches&#x2F;junghans-radio...</a>

I just wish this time sync feature wasn’t limited to only Western world and East Asia.<p>A nice feature, but not usable in Thailand, where I live.

I&#x27;m curious why we don&#x27;t just use GPS&#x27;s UTC time broadcast to set time? I understand that using GPS to track satellites and find location is power hungry, but I can&#x27;t imagine that simply receiving a time and setting a clock is any more power hungry than this system.

Got a Pro-Trek PRW-30, and this works flawlessly.<p>It syncs almost every night, and takes into account DST just fine.

I’m from Germany — we drove to Arizona from California a few years ago and were too late for check in which was super annoying. I got a SEIKO Astron watch that synchronizes the time via GPS after that and couldn’t be more satisfied; it also runs on solar and holds a charge of 6 months for when there’s no sun (i.e. Antarctica). This watch is so precise it’s my absolute time reference. When I’m traveling I keep my Apple Watch at home and only wear the SEIKO; the Apple Watch is pointless anyway if you’re stuck in the desert for more than a few days.

I have the all black GW-2310FB. I’ll be honest, the gray digits on black background can be a little impractical in low light (it does have a very good backlit if you press the button). But it looks awesome and I have no regrets. Love it. And for those of you that are militant about your IDE’s dark mode, this could be the watch for you too. <a href="https:&#x2F;&#x2F;www.casio.com&#x2F;us&#x2F;watches&#x2F;gshock&#x2F;product.GW-2310FB-1&#x2F;" rel="nofollow noreferrer">https:&#x2F;&#x2F;www.casio.com&#x2F;us&#x2F;watches&#x2F;gshock&#x2F;product.GW-2310FB-1&#x2F;</a>

Great technology, works fine, at least 10-20 years old now.

That was (and still is) a great technology, but in the last couple of years Casio has bluetooth-enabled watches that can sync with your phone (that is syncing with the base station, which syncs with GPS). Bluetooth adds about $10-20 on top, but works indoors and outdoors, day or night or on-demand, all around the world.<p>(The usual Casio G-Shock time deviation is under 20 seconds per month, so there&#x27;s that.)

Had the GW9400. Now using GWG2000<p>Works flawless in Seoul and Beijing. A month in South Bay and flawless too.<p>There is no signal for this back home in Singapore. What I do - since we also don&#x27;t know when they&#x27;re gonna shut off the radio towers - is use an app on my Tab S8 Ultra, set my watch&#x27;s time zone to Tokyo, leave watch right next to speaker and go do something else. After some beeps and minutes : my watch time is readjusted.<p>No fiddling.

I have a citizen watch with this. Tends to keep time just fine. Though so did all my other quartz watches until the battery dies

I&#x27;ve been using a radio controlled clock for many years. At some point I noticed it was more frequently reporting it had been unable to sync properly. I&#x27;d never noticed this before. Turned out the UK time signal had moved from Rugby to Anthorn. It really seemed to negatively impact reception.

I have Casio GW-M5600. It&#x27;s a perfect watch.<p>- Looks like classic G-Shock.<p>- shows correct time always (time sync)<p>- never runs out of battery (solar charging).

Cool to have this multiband technology, but what about the southern hemisphere? Assuming they have time signal transmitters, too: Do watch manufacturers have different SKUs that can receive signals in the southern hemisphere? Is it possible to have a watch that receives these signals truly worldwide?

I wish Casio would bring back the WV-300 form factor: <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=t79GeZkTJLY">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=t79GeZkTJLY</a><p>The closest modern replacement is the GMW-B5000, but that&#x27;s quite large and expensive compared to what they were doing in 2008.

Good read on the accuracy of radio controlled clocks: <a href="https:&#x2F;&#x2F;tf.nist.gov&#x2F;general&#x2F;pdf&#x2F;2429.pdf" rel="nofollow noreferrer">https:&#x2F;&#x2F;tf.nist.gov&#x2F;general&#x2F;pdf&#x2F;2429.pdf</a>

I&#x27;d be curious to see a proper signal map for this service. I&#x27;ve been the proud owner of a Casio Oceanus for a little over a year now. I can count on one hand the number of times the watch has synchronized via radio.

For anyone in the Iberian peninsula, I&#x27;ve had some luck using UK&#x27;s radio on mine. Be mindful to try it at night, and if the meteorological conditions allow.<p>Hope there were more stations...

I have a wall clock that syncs with an atomic clock in Colorado, which was cool at first but I live in Arizona now which doesn’t observe daylight savings so it’s often wrong by an hour now.

Either get Gshock GWM5610-1 which is solar and synced for good price, or get Garmin Instict Solar for all bells and whistles and also unlimited power in theory.

I had one of these when I was a child. I now have an Apple Watch on my wrist, go figure.

not working in SEA, though :&#x2F; there are some tricks with apps synthesizing a electromagnetic radio signal via speaker activity but i never got this to work.

I have one in the south of Spain and it doesn&#x27;t work practically anywhere and definitely not where I sleep (since it can be set to synchronise after midnight automatically)<p>I bought it in part because of this feature and it was quite sad. These quartz watches are good but they still drift substantially after a few months.<p>Thankfully I heard of the DCF77 emulator app thanks to this thread and I will use it.