On 19/11/2021 22.19, Martin Brown wrote:> On 19/11/2021 18:48, Carlos E.R. wrote: >> Hi, >> >> I'd like to find a wall clock, say kitchen clock, that instead of >> syncing using the DCF radio station >> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >> >> I may have asked about this before. >> >> Problem is, that here in Spain the DCF signal is so weak that clocks >> can only sync during 01 to 05 AM, and often not even that, so that my >> clocks can be in error for minutes of even hours, not getting >> corrected in weeks. > > A decent quartz crystal clock should be good to a few tens of seconds a > month at most. There is something wrong if it runs out more than that.Specs are normally up to 4 seconds off per day, thus easily a minute a month; thus by the time I have to adjust summer/winter time, they are easily 5 minutes off. And I hate having to adjust summer/winter time. I also have 2 "automatic" DCF clocks, radio adjusted, and they don't work. So I specifically want clocks that adjust via Internet, NTP protocol, nothing else is valid for me. That's my question, please. Wall clocks for kitchen or elsewhere that sync using WiFi. -- Cheers, Carlos.
Seeking for a wall clock
Started by ●November 19, 2021
Reply by ●November 19, 20212021-11-19
Reply by ●November 19, 20212021-11-19
On Fri, 19 Nov 2021 21:45:05 +0100, "Carlos E.R." <robin_listas@es.invalid> wrote:>On 19/11/2021 20.35, Tauno Voipio wrote: >> On 19.11.21 20.48, Carlos E.R. wrote: >>> Hi, >>> >>> I'd like to find a wall clock, say kitchen clock, that instead of >>> syncing using the DCF radio station >>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>> >>> I may have asked about this before. >>> >>> Problem is, that here in Spain the DCF signal is so weak that clocks >>> can only sync during 01 to 05 AM, and often not even that, so that my >>> clocks can be in error for minutes of even hours, not getting >>> corrected in weeks. >>> >>> So I wonder if somebody makes some sort of ready made clock that uses >>> internet for syncing and which can be put on a wall. Or a kit. >>> >>> Possibly it would run Android. >>> >>> For example I found one or two bedside alarm clocks (Lenovo Smart >>> Clock Essential, with microphone switched off). But nothing for the >>> wall. I really do not want a smart clock with a microphone listening, >>> I just want a clock, perhaps with a thermometer or weather app. >>> >>> >>> A possibility would be dedicate an old tablet to this. Or an ebook >>> reader (some have apps) >>> >>> I heard of people doing things like that with a Pi or whatever, but I >>> don't look forward to that, somehow, from scratch. A kit, may be. >>> >>> >>> Maybe a DCF repeater? >>> >> >> There are schematics around, at least for WWW and WWWH (60 kHz), which >> can be changed for 77.5 kHz. You'll need to place the reception antenna >> far enough to prevent feedback and oscillation of the unit. > >I feared that :-( > >> >> If you find a clock, please tell us. I'm 1540 km from Mainflingen, but >> opposite direction compared to you (Helsinki, Finland). > >Ok! :-) >It's pretty easy to make an analog 77.5 KHz amplifier repeater to increase the allowed distance to the transmitter at Mainflingen. There are some necessary tricks. First, use tuned ferrite-rods for both repeater receive and repeater transmit antennas. The bandwidth is maybe 10 Hz Second, space them at least ten meters apart. Third, make them perpendicular to one another. Forth, shield everything, so no electrostatic coupling. The repeater input rod is oriented for maximum reception from Mainflingen. The repeater output rod is perpendicular, and the clock is nearby, with its rod parallel to the repeater output rod. Joe Gwinn
Reply by ●November 19, 20212021-11-19
On Fri, 19 Nov 2021 21:44:24 +0100, "Carlos E.R." <robin_listas@es.invalid> wrote:>On 19/11/2021 20.59, John Larkin wrote: >> On Fri, 19 Nov 2021 19:48:21 +0100, "Carlos E.R." >> <robin_listas@es.invalid> wrote: >> >>> Hi, >>> >>> I'd like to find a wall clock, say kitchen clock, that instead of >>> syncing using the DCF radio station >>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>> >>> I may have asked about this before. >>> >>> Problem is, that here in Spain the DCF signal is so weak that clocks can >>> only sync during 01 to 05 AM, and often not even that, so that my clocks >>> can be in error for minutes of even hours, not getting corrected in weeks. >>> >>> So I wonder if somebody makes some sort of ready made clock that uses >>> internet for syncing and which can be put on a wall. Or a kit. >>> >>> Possibly it would run Android. >>> >>> For example I found one or two bedside alarm clocks (Lenovo Smart Clock >>> Essential, with microphone switched off). But nothing for the wall. I >>> really do not want a smart clock with a microphone listening, I just >>> want a clock, perhaps with a thermometer or weather app. >>> >>> >>> A possibility would be dedicate an old tablet to this. Or an ebook >>> reader (some have apps) >>> >>> I heard of people doing things like that with a Pi or whatever, but I >>> don't look forward to that, somehow, from scratch. A kit, may be. >>> >>> >>> Maybe a DCF repeater? >> >> A cheap modern XO clock should be stable to a few PPM. >> >> Replace the batteries and set it every 6 months. > >Yeah, well, that's what I use, a plain analog clock, Xtall controlled. >Still, goes of more than a minute by the time I have to adjust >summer/winter time again. I want improvement :-)It may have a trimmer cap inside. And probably a 32768 Hz crystal. You could potentially trim it. -- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in certainties. Francis Bacon
Reply by ●November 19, 20212021-11-19
On 19/11/2021 23.33, Joe Gwinn wrote:> On Fri, 19 Nov 2021 21:45:05 +0100, "Carlos E.R." > <robin_listas@es.invalid> wrote: > >> On 19/11/2021 20.35, Tauno Voipio wrote: >>> On 19.11.21 20.48, Carlos E.R. wrote: >>>> Hi, >>>> >>>> I'd like to find a wall clock, say kitchen clock, that instead of >>>> syncing using the DCF radio station >>>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>>> >>>> I may have asked about this before. >>>> >>>> Problem is, that here in Spain the DCF signal is so weak that clocks >>>> can only sync during 01 to 05 AM, and often not even that, so that my >>>> clocks can be in error for minutes of even hours, not getting >>>> corrected in weeks. >>>> >>>> So I wonder if somebody makes some sort of ready made clock that uses >>>> internet for syncing and which can be put on a wall. Or a kit. >>>> >>>> Possibly it would run Android. >>>> >>>> For example I found one or two bedside alarm clocks (Lenovo Smart >>>> Clock Essential, with microphone switched off). But nothing for the >>>> wall. I really do not want a smart clock with a microphone listening, >>>> I just want a clock, perhaps with a thermometer or weather app. >>>> >>>> >>>> A possibility would be dedicate an old tablet to this. Or an ebook >>>> reader (some have apps) >>>> >>>> I heard of people doing things like that with a Pi or whatever, but I >>>> don't look forward to that, somehow, from scratch. A kit, may be. >>>> >>>> >>>> Maybe a DCF repeater? >>>> >>> >>> There are schematics around, at least for WWW and WWWH (60 kHz), which >>> can be changed for 77.5 kHz. You'll need to place the reception antenna >>> far enough to prevent feedback and oscillation of the unit. >> >> I feared that :-( >> >>> >>> If you find a clock, please tell us. I'm 1540 km from Mainflingen, but >>> opposite direction compared to you (Helsinki, Finland). >> >> Ok! :-) >> > > It's pretty easy to make an analog 77.5 KHz amplifier repeater to > increase the allowed distance to the transmitter at Mainflingen. There > are some necessary tricks. First, use tuned ferrite-rods for both > repeater receive and repeater transmit antennas. The bandwidth is > maybe 10 Hz Second, space them at least ten meters apart. Third, > make them perpendicular to one another. Forth, shield everything, so > no electrostatic coupling. > > The repeater input rod is oriented for maximum reception from > Mainflingen. The repeater output rod is perpendicular, and the clock > is nearby, with its rod parallel to the repeater output rod.Hum. Too complicated, unless someone sells a prepared kit. It has been decades since I do anything of the sort. -- Cheers, Carlos.
Reply by ●November 19, 20212021-11-19
On Friday, 19 November 2021 at 18:32:11 UTC-8, Carlos E.R. wrote: ...> > The repeater input rod is oriented for maximum reception from > > Mainflingen. The repeater output rod is perpendicular, and the clock > > is nearby, with its rod parallel to the repeater output rod. > Hum. Too complicated, unless someone sells a prepared kit. It has been > decades since I do anything of the sort.... You don't need a Raspberry Pi to synchronize with NTP. Here is a design using an ESP8266 programmed in the Arduino IDE. https://www.instructables.com/ESP8266-LED-Matrix-Clock/ kw
Reply by ●November 20, 20212021-11-20
On Friday, November 19, 2021 at 10:52:11 AM UTC-8, Carlos E.R. wrote:> Hi, > > I'd like to find a wall clock, say kitchen clock, that instead of > syncing using the DCF radio station > (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync.An off-the-shelf solution is the venerable Chumby <https://www.thechumbystore.com> which is kinda open-source and somewhat supported, with Sony and other manufacturers sometimes supporting the hardware. A NNTP clock is the base application for these.
Reply by ●November 20, 20212021-11-20
On 19/11/2021 21:52, Carlos E.R. wrote:> On 19/11/2021 22.19, Martin Brown wrote: >> On 19/11/2021 18:48, Carlos E.R. wrote: >>> Hi, >>> >>> I'd like to find a wall clock, say kitchen clock, that instead of >>> syncing using the DCF radio station >>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>> >>> I may have asked about this before. >>> >>> Problem is, that here in Spain the DCF signal is so weak that clocks >>> can only sync during 01 to 05 AM, and often not even that, so that my >>> clocks can be in error for minutes of even hours, not getting >>> corrected in weeks. >> >> A decent quartz crystal clock should be good to a few tens of seconds >> a month at most. There is something wrong if it runs out more than that. > > Specs are normally up to 4 seconds off per day, thus easily a minute a > month; thus by the time I have to adjust summer/winter time, they are > easily 5 minutes off.There is usually a trimmer on the back or in the case so you adjust it to be within about 2ppm if you have the patience. A little wheel with a legend along the lines of "- <-> +" though sometimes just an exposed screwhead. I assume here that the clock will be indoors and not subject to violent changes in temperature.> And I hate having to adjust summer/winter time. > > I also have 2 "automatic" DCF clocks, radio adjusted, and they don't work.Buy better ones then.> So I specifically want clocks that adjust via Internet, NTP protocol, > nothing else is valid for me. That's my question, please. Wall clocks > for kitchen or elsewhere that sync using WiFi.It is an ideal DIY electronics project if you you must have one. -- Regards, Martin Brown
Reply by ●November 20, 20212021-11-20
On 19/11/2021 23:54, John Larkin wrote:> On Fri, 19 Nov 2021 21:44:24 +0100, "Carlos E.R." > <robin_listas@es.invalid> wrote: > >> On 19/11/2021 20.59, John Larkin wrote: >>> On Fri, 19 Nov 2021 19:48:21 +0100, "Carlos E.R." >>> <robin_listas@es.invalid> wrote: >>> >>>> Hi, >>>> >>>> I'd like to find a wall clock, say kitchen clock, that instead of >>>> syncing using the DCF radio station >>>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>>> >>>> I may have asked about this before. >>>> >>>> Problem is, that here in Spain the DCF signal is so weak that clocks can >>>> only sync during 01 to 05 AM, and often not even that, so that my clocks >>>> can be in error for minutes of even hours, not getting corrected in weeks. >>>> >>>> So I wonder if somebody makes some sort of ready made clock that uses >>>> internet for syncing and which can be put on a wall. Or a kit. >>>> >>>> Possibly it would run Android. >>>> >>>> For example I found one or two bedside alarm clocks (Lenovo Smart Clock >>>> Essential, with microphone switched off). But nothing for the wall. I >>>> really do not want a smart clock with a microphone listening, I just >>>> want a clock, perhaps with a thermometer or weather app. >>>> >>>> >>>> A possibility would be dedicate an old tablet to this. Or an ebook >>>> reader (some have apps) >>>> >>>> I heard of people doing things like that with a Pi or whatever, but I >>>> don't look forward to that, somehow, from scratch. A kit, may be. >>>> >>>> >>>> Maybe a DCF repeater? >>> >>> A cheap modern XO clock should be stable to a few PPM. >>> >>> Replace the batteries and set it every 6 months. >> >> Yeah, well, that's what I use, a plain analog clock, Xtall controlled. >> Still, goes of more than a minute by the time I have to adjust >> summer/winter time again. I want improvement :-) > > It may have a trimmer cap inside. And probably a 32768 Hz crystal. You > could potentially trim it.All of the cheap xtal clock mechanisms I have ever seen have an adjuster on the back. The odd one does it digitally calibrated at manufacture against a reference second by tweaking the length of a second every now and then to compensate up or down by a few ppm. Long term average over a whole number of days can be made very good indeed this way. -- Regards, Martin Brown
Reply by ●November 20, 20212021-11-20
On a sunny day (Sat, 20 Nov 2021 10:50:17 +0000) it happened Martin Brown <'''newspam'''@nonad.co.uk> wrote in <snajtm$1nb9$1@gioia.aioe.org>:>On 19/11/2021 23:54, John Larkin wrote: >> On Fri, 19 Nov 2021 21:44:24 +0100, "Carlos E.R." >> <robin_listas@es.invalid> wrote: >> >>> On 19/11/2021 20.59, John Larkin wrote: >>>> On Fri, 19 Nov 2021 19:48:21 +0100, "Carlos E.R." >>>> <robin_listas@es.invalid> wrote: >>>> >>>>> Hi, >>>>> >>>>> I'd like to find a wall clock, say kitchen clock, that instead of >>>>> syncing using the DCF radio station >>>>> (https://en.wikipedia.org/wiki/DCF77), uses WiFi (ie, internet) to sync. >>>>> >>>>> I may have asked about this before. >>>>> >>>>> Problem is, that here in Spain the DCF signal is so weak that clocks can >>>>> only sync during 01 to 05 AM, and often not even that, so that my clocks >>>>> can be in error for minutes of even hours, not getting corrected in weeks. >>>>> >>>>> So I wonder if somebody makes some sort of ready made clock that uses >>>>> internet for syncing and which can be put on a wall. Or a kit. >>>>> >>>>> Possibly it would run Android. >>>>> >>>>> For example I found one or two bedside alarm clocks (Lenovo Smart Clock >>>>> Essential, with microphone switched off). But nothing for the wall. I >>>>> really do not want a smart clock with a microphone listening, I just >>>>> want a clock, perhaps with a thermometer or weather app. >>>>> >>>>> >>>>> A possibility would be dedicate an old tablet to this. Or an ebook >>>>> reader (some have apps) >>>>> >>>>> I heard of people doing things like that with a Pi or whatever, but I >>>>> don't look forward to that, somehow, from scratch. A kit, may be. >>>>> >>>>> >>>>> Maybe a DCF repeater? >>>> >>>> A cheap modern XO clock should be stable to a few PPM. >>>> >>>> Replace the batteries and set it every 6 months. >>> >>> Yeah, well, that's what I use, a plain analog clock, Xtall controlled. >>> Still, goes of more than a minute by the time I have to adjust >>> summer/winter time again. I want improvement :-) >> >> It may have a trimmer cap inside. And probably a 32768 Hz crystal. You >> could potentially trim it. > >All of the cheap xtal clock mechanisms I have ever seen have an adjuster >on the back. The odd one does it digitally calibrated at manufacture >against a reference second by tweaking the length of a second every now >and then to compensate up or down by a few ppm. Long term average over a >whole number of days can be made very good indeed this way.It is interesting to know that the clock on my microwave oven (make Whirlpool), that I think uses 50Hz mains, stays to within seconds over a long time, Same for my Sony radio clock. Few years ago there was a minutes long error due to 50Hz drift between power stations.. and it showed, You realy do not normally need any more accuracy, but until the politiCsians stop the summer / winter time crap you have have to adjust those things twice a year. I am all for UTC everywhere worldwide. Just a matter of getting used to locally, but much easier globally, and no clock change stress.
Reply by ●November 20, 20212021-11-20
On 20/11/2021 10:56, Jan Panteltje wrote:> On a sunny day (Sat, 20 Nov 2021 10:50:17 +0000) it happened Martin Brown > <'''newspam'''@nonad.co.uk> wrote in <snajtm$1nb9$1@gioia.aioe.org>: > >> On 19/11/2021 23:54, John Larkin wrote: >>> On Fri, 19 Nov 2021 21:44:24 +0100, "Carlos E.R." >>> <robin_listas@es.invalid> wrote:>>>> Yeah, well, that's what I use, a plain analog clock, Xtall controlled. >>>> Still, goes of more than a minute by the time I have to adjust >>>> summer/winter time again. I want improvement :-) >>> >>> It may have a trimmer cap inside. And probably a 32768 Hz crystal. You >>> could potentially trim it. >> >> All of the cheap xtal clock mechanisms I have ever seen have an adjuster >> on the back. The odd one does it digitally calibrated at manufacture >> against a reference second by tweaking the length of a second every now >> and then to compensate up or down by a few ppm. Long term average over a >> whole number of days can be made very good indeed this way. > > It is interesting to know that the clock on my microwave oven (make Whirlpool), > that I think uses 50Hz mains, stays to within seconds over a long time, > Same for my Sony radio clock.Long term mains frequency is effectively locked back to atomic clocks. They have to keep the long term average within very tight bounds and so typically run the frequency faster overnight when loads are lighter (the older mechanical systems tend to do this slightly anyway). It used to annoy astronomers back in the day when many drives were ac mains synchronous motors (and they would run fast by ~1% at night). Today everything is dc servo based and autoguided so it is irrelevant.> Few years ago there was a minutes long error due to 50Hz drift between power stations.. > and it showed, > You realy do not normally need any more accuracy, but until the politiCsians > stop the summer / winter time crap you have have to adjust those things twice a year. > I am all for UTC everywhere worldwide. > Just a matter of getting used to locally, but much easier globally, and no clock change stress.At higher latitudes the clock changes sort of make sense. -- Regards, Martin Brown
