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I wanted a clock that never needed setting. Things escalated

arstechnica.com

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Re: I wanted a clock that never needed setting. Things escalated

#151

Post by dingaling »

bArray wrote: post #103

If you're in the UK, just use the MSF radio signal to sync your clock [1]. > The end result exactly matched my expectations—the best criterion for success that I can think of. With an LLM providing the heavy code lifting and the CAD work, I think I spent more time waiting on supplies to arrive than on anything else—something attributable to my lack of planning and the ease of next-day delivery. I think the author rob…

Unfortunately, being a weak VLF signal, it's very susceptible to interference and screening.

My MSF clocks at the front of the house keep perfectly synced, the ones deeper in the house wander hopelessly

Re: I wanted a clock that never needed setting. Things escalated

#152

Post by WillAdams »

dingaling wrote: post #150
WillAdams wrote: post #120

Earlier quoted context omitted.

There is a charming "Literary Quote" clock: https://www.uncommongoods.com/product/literary-clock and I've often wished that it had a set of quotes for such approximate times.

https://github.com/elegantalchemist/literaryclock

Apparently, since the Kickstarter for Literary Clock, there has been an update of quotes w/ approximate times.

Neat project though! Will keep it in mind for the next time I update a Kindle.

Re: I wanted a clock that never needed setting. Things escalated

#153

Post by pgh »

dingaling wrote: post #149
all2 wrote: post #145

Earlier quoted context omitted.

My solution to this is to not have clocks in my house at all. This has nothing to do with the fact that I still haven't figured out how to set the time on my microwave. :D

Clocks on microwaves seems to be a curiously American custom, driven by the fact that US outlet sockets generally don't have switches. In Europe, and the UK particularly, every socket has a switch so the microwave is turned off after each use.

It might be switched off after each use in your household but it’s definitely not in others. Neither is the toaster, nor kettle.

Re: I wanted a clock that never needed setting. Things escalated

#154

Post by threeio »

o_enix_o wrote: post #82
mikewarot wrote: post #72

I too find myself going down the time-nut rabbit hole. I want a perfect 10 Mhz reference, not necessarily a time of day clock. I was tempted to go the Atomic Clock route, based on actual cesium oscillators, having found a cheapish ($999) used CSAC on ebay[1]. However, once I started digging into the data sheets[2], I found something unacceptable, Pin 1, labeled "Tune", an analog tuning input. It was then that I learn…

Fascinating, can you share why you need a 10Mhz reference?

(for me) Sometimes your job might make you run reference time for a large service provider... and then you need multiple reference signals... and then you realize you have spares that are going to be thrown away... and suddenly your home lab becomes way too geeky for you to admit to 99.999999989% of your friends... unless they also are on the same time email list as you ;)

Re: I wanted a clock that never needed setting. Things escalated

#155

Post by mikewarot »

o_enix_o wrote: post #82
mikewarot wrote: post #72

I too find myself going down the time-nut rabbit hole. I want a perfect 10 Mhz reference, not necessarily a time of day clock. I was tempted to go the Atomic Clock route, based on actual cesium oscillators, having found a cheapish ($999) used CSAC on ebay[1]. However, once I started digging into the data sheets[2], I found something unacceptable, Pin 1, labeled "Tune", an analog tuning input. It was then that I learn…

Fascinating, can you share why you need a 10Mhz reference?

10 MHz is the usual frequency that test equipment uses for external reference. If I could get more than one cheap enough I could do some very interesting home physics experiments.

For example, does time pass differently inside a can at a million volts potential relative to ground? Both positive and negative rate measurements.

What about inside a large "A" field at the heart of a large toroid?

I suppose I could trim them to the same frequency before the experiments, but still $1000 for hone lab experiments is out of my price range.

Re: I wanted a clock that never needed setting. Things escalated

#156

Post by hn_submit »

I find it wasteful to make a simple clock running a full-scale Linux distro just to fetch and display the time. And it's running Python too, which is an interpreted language which is a 100 times slower than C or assembly.

I didn't look at the code but if it's not interrupt driven it will be wasting even more power.

Re: I wanted a clock that never needed setting. Things escalated

#157

Post by RetroTechie »

MathMonkeyMan wrote: post #67

This is a harder problem than it seems. I've been thinking and reading about it for a side project, but haven't done much testing yet. There are a few places to get the current time: - on-board real-time clock (RTC) connected to a continuous power source (e.g. button battery) - GPS - Colorado WWVB signal (60 KHz), Frankfurt DCF-77 (77.5 KHz), Cumbria NPL (60 KHz) - the internet (NTP, HTTPS servers, etc.) - mobile int…

> The best option is the RTC. Buy a DS3231, hook it up to your microcontroller and a button battery, and forget about it for a few years.

RTC ICs are for use in bigger systems where main CPUs have other things to do. If you design a clock around a microcontroller dedicated to the task, that microcontroller can do the timekeeping all by itself. No extra IC needed.

Also quartz oscillators (ones built from discrete parts) can be trimmed. If you'd take the trouble, a cheapo quartz oscillator can go from 20..50 ppm to perhaps a few ppm worst case. Which as you point out is in the order of a minute per year. If that's not good enough AND power budget is available, an oven-controlled quartz oscillator improves on that.

All that online / GPS / radio controlled stuff is for convenience only (daylight saving!). Not needed just to have an accurate clock.

Oh and there's using AC mains frequency as timebase.

Re: I wanted a clock that never needed setting. Things escalated

#158

Post by deweywsu »

Here, the author used a much less domain-specific LLM and it sounds like it produced good results. This made me wonder about other's experiences using LLMs to produce both CAD and schematics/pcb layout. Are there any good references people could leave of the tools people are using for this kind of AI-assisted design that are producing acceptable results today?

I tried Flux.ai for electronics for example, and found it too confusing and not as helpful as I'd hoped. I'm hopeful that I can lean on generic AI tools in the future to augment some of the detailed design (while still applying thorough oversight and review of what's produced based on experience).

Re: I wanted a clock that never needed setting. Things escalated

#159

Post by Animats »

dewarrn1 wrote: post #113
Animats wrote: post #19

It's a clock. Does it really have to have remote updating, a command line interface, an Internet connection, and HomeKit integration? That's too IoT. I have three La Crosse clocks that run off the NIST time signal out of Boulder, CO, and need their AA battery replaced maybe once a year. The real challenge is running such a thing on a small battery for a year. I once made a small clock that displayed "A LITTLE AFTER S…

It's not quite the same, but your prose clock solution reminded me of this: https://www.authorandco.com/products/author-clock .

That is very nice. A large version of that would be a good bookstore window display for a busy street. It's too bad the Author Clock doesn't have a video output for a larger display.

The "a little after six" clock idea was from a old New Yorker cartoon. Searches for the cartoon have not been successful, because the original had no caption, and the Cartoon Bank search engine is a textual search. If anyone can find it, please let me know.

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