I saw this multi-zone clock mentioned today : https://www.electronics-lab.com/arduino-nano-33-iot-based-ntp-world-clock/
It's not a ready-to-go product nor is it as simple as 4 COTS clocks. It's possibly also harder to put together than Didier's suggestion, which could run on a raspberyy pi with an LCD screen. However the design is presented as something to copy so it's at least not such an open-ended project as making it yourself from arduinos. I'm not sure what physical format you wanted. I read it as a row of clocks rather than a square, arranged to fit on a common screen. Perhaps that's not important. However if you're interested in something less computer-like, have a look on aliexpress for 'supermarket shelf edge display' - there are a number of very wide but low-height displays available now. On Sun, Jan 10, 2021 at 10:08 AM Didier Juges <[email protected]> wrote: > Well, the latency in the php web page I posted earlier bugged the heck out > of me so I redid it the "right" way: > > > http://www.ko4bb.com/js/clock/?tz=America/Los_Angeles,Europe/Paris,Asia/Novosibirsk > > Now the web page loads a Javascript program that uses the local machine's > time, the internet is only involved when loading the page initially, saving > many many electrons! > If you keep the local machine clock in sync with any of the many ntp or > sntp apps, the time will be correct (but not necessarily exactly on the > second, that will be for the next version...) > > Here also you can have as many time zones as you want, just add them on the > command line with a comma separator. > Time zone definitions can be found on the Wikipedia page: > https://en.wikipedia.org/wiki/List_of_tz_database_time_zones > > Didier KO4BB > > PS: the code (it uses the luxon javascript library): > > <!DOCTYPE html "-//W3C//DTD XHTML 1.0 Strict//EN" > "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd";> > <html xmlns="http://www.w3.org/1999/xhtml";> > <head> > <title>World Clock</title> > <script type="text/javascript" src="luxon.js"></script> > <script> > var DateTime = luxon.DateTime; > var out_str=""; > function getParameterByName( name, url = window.location.href ){ > name = name.replace( /[\[\]]/g, '\\$&' ); > var regex = new RegExp( '[?&]' + name + '(=([^&#]*)|&|#|$)' ), > results = regex.exec( url ); > if( !results) return null; > if( !results[2] ) return ''; > return decodeURIComponent( results[2].replace( > /\+/g, ' ' )); > } > function load(){ > setInterval( function(){ putAllTimes();}, 1000 ); > } > function putAllTimes(){ > DateTime = luxon.DateTime; > var tzs = getParameterByName( 'tz' ); > var tza = tzs.split(",") > tza.forEach( putOneTime ); > document.getElementById( 'time' ).innerHTML = out_str; > } > function putOneTime( tz, index ){ > var ttime = DateTime.fromObject({zone: tz}); > if( index == 0 ) > out_str = tz + ": " + > ttime.toLocaleString(DateTime.DATETIME_MED_WITH_SECONDS) + "<p>"; > else > out_str += tz + ": " + > ttime.toLocaleString(DateTime.DATETIME_MED_WITH_SECONDS) + "<p>"; > } > </script> > </head> > <body onload="load()"> > <h2>KO4BB's World Clock</h2> > <div id="time"> > </div> > </body></html> > > > > On Sat, Jan 9, 2021 at 5:23 PM Mark Spencer <[email protected]> > wrote: > > > This thread prompted me to turn on my old IPad1 and I confirmed the > > Emerald Time app I downloaded many years ago is still functional. > > > > > > Mark Spencer > > [email protected] > > 604 762 4099 > > > > > On Jan 8, 2021, at 12:16 PM, paul swed <[email protected]> wrote: > > > > > > Old iphones maybe cheap or you may have one. Since LTE4 I guess is in > the > > > process of being turned off old iphone 5s will no longer work. > > > My wife now has a iphone 6 and I have ordered a battery for the 5 > because > > > it is a useful widget that looks good and can use wi-fi. > > > Granted thats a small screen and thats why earlier I was suggesting one > > of > > > the larger nice tablets. I have an Asus tablet driving a 27" screen 24 > X > > 7. > > > I am actually looking at clock programs to load onto the asus. Just > > started > > > looking last week. > > > Regards > > > Paul > > > WB8TSL > > > > > >> On Fri, Jan 8, 2021 at 2:50 PM John Sloan <[email protected]> wrote: > > >> > > >> I’d investigate whether there was an Android “World Clock” app whose > > >> display had your requirements, then buy an Android tablet in your > price > > >> range and with the appropriate form factor. (I like the “World Clock” > > app > > >> on my iPhone, but I’ve never encountered a cheap iPhone.) > > >> > > >> -- > > >> J. L. Sloan Digital Aggregates Corp. > > >> +1 303 940 9064 (O) 3440 Youngfield St. #209 > > >> +1 303 489 5178 (M) Wheat Ridge CO 80033 USA > > >> [email protected] http://www.diag.com <http://www.diag.com/> > > >> > > >>> On Jan 8, 2021, at 8:29 , [email protected] wrote: > > >>> > > >>> [time-nuts] small multi-timezone display > > >> > > >> _______________________________________________ > > >> time-nuts mailing list -- [email protected] > > >> To unsubscribe, go to > > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > >> and follow the instructions there. > > > _______________________________________________ > > > time-nuts mailing list -- [email protected] > > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > and follow the instructions there. > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
