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- Hacker News
- >"...but damned if I could find one with a red seven-segment display that I liked..."
Funny but I have one which updates time "via the cosmic ether", has big red 7-seg LEDs and as cherry on top it has laser LED based projector that displays same big red 7 seg digits on whatever surface one points it to - ceiling in my case. I bought it decades ago in RadioShack
by FpUser - I just use one those awtrix clones made by ulanzi, multiple open source firmwares for it since esp32 based. NTP, http api for displaying alerts, and mqtt support
No need for me to reinvent the wheel, works a treat mounted above my monitor
- Using a supercomputer to power a clock, now that is overengineering.
I made a LED matrix clock using esp32 syncing time with ntp server every hour and an external RTC to do time keeping if my network is down, and it runs perfectly for years, with accuracy +-1s to time.is. Never have to do setting except the first boot to setup wifi.
by mrheosuper - The author's primary lament is clocks that cannot withstand power flickers, yet every sub-$10 mains voltage clock from Walmart and Target that I've ever seen will take a 9V battery to make them resilient against such power interruptions.
Might want to flip the clock over and check for a battery door before starting next time.
by pudgywalsh - That might do to keep it within a minute during power loss, and maybe that's good enough for most people. But if you really want to be worry-free you need something more high tech.
It would be worth it for me not to have to touch it twice a year for DST.
by mark-r - 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 learned that while the Cesium vapor cells were accurate, they aged, and drifted, unlike a properly degaussed and Zeeman harmonic calibrated Cesium Beam atomic clock, which is a primary standard.
Further demotivating was learning they have a 5-10 year service life. That's a lot of money to pay for what's essentially a better OXCO.
I'll stick with GPS disciplined oscillators for now.
[1] https://www.ebay.com/itm/327134074179
[2] https://www.mouser.com/datasheet/2/523/Microsemi_CSAC_Space_...
by mikewarot - Fascinating, can you share why you need a 10Mhz reference?by o_enix_o
- I feel this article's premise too much. That's exactly the sort of clock I wanted to get my mom as a gift.
Why is it so dang impossible to find a not trash simple LED clock that's 'large print', 'the right color', and not annoyingly too bright?
A deluxe model might include a day of the week bar or dot and a month / day in month number (smaller than the time, mostly people care about the time)
by mjevans - Did you look at memory clocks?by maxerickson
- I found the following that works quite well
https://www.amazon.com/dp/B0CWKYRS84
(the LEDs come in different colors)
by ninju - My parents rely on mechanical clocks, adjusting and ‘winding’ weights almost every day, they take great joy and pride from the fiddling. It’s fun to hear the clocks announce the hour and slowly hear them drift over time.by thenthenthen
- I needed the same thing, so I made one:
https://www.stavros.io/posts/i-made-another-little-bedside-c...
by stavros - I think too bright would be an issue with any LED display. Even lights on my modem in a different room are a bit much, I turn it off at night.by incompatible
- I've had the same struggle. There are some decent LED clocks with up to 1" displays (high), but any further and you get weird colors or glaringly-bright displays.
The best options are expensive clock displays from like Time Machines, MasterClock, etc... but they are not cheap and not meant for consumers.
by geerlingguy - 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 robbed themselves of a deeper understanding.
[1] https://www.npl.co.uk/products-services/time-frequency/msf-r...
by bArray - 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
by dingaling - This reminded of this other clock project: https://mitxela.com/projects/precision_clock_mk_iv
Also: I reckon the closest best-value watch alternative that ticks most(?) of the author's boxes is the Casio GW-M5610-1ER, so long as you are inside a radio-controlled time area.
by sudb - Casio also has cheaper "wave ceptor" models that do this. If you get one from Japan you can get a nice-looking rectangular model.
- The atomic time radio station WWVB does in fact broadcast a daylight saving time bit. A good atomic time clock should accurately update for DST (though Amazon reviews for a clock like this one is pretty mixed: https://www.amazon.com/Crosse-Technology-617-249-Curved-Atom...)by linehedonist
- My La Crosse wall clock does support the DST bit, the switch on the back only sets whether you live somewhere that recognizes it or not. Twice a year I try and stay up to watch the clock hands zoomin around during the changeoverby wpm
- "One, the path not taken, started with an Arduino or Arduino-like microcontroller. The other began with a Raspberry Pi or Pi-like computer-y thing. I went with the Pi, variously using both a Raspberry Pi Zero W and Zero 2 W."
Ok, so instead of bumping your clock +- one hour twice a year you preferred distro upgrades?
by sasaf5 - 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 SIX" and such, changing its text every five minutes. Needed a power connection, though.
by Animats - I mean, I made a clock with remote updating. No command line or HomeKit... Internet is handy because it reads an iCal feed to set the alarm.
I thought the remote updating would be more convenient than bringing it to the dev computer, but I dunno, it's really not... Except for the one I sent to a friend, but I think she politely stopped asking for help cause it didn't really work for her.
It has issues, but it might be a useful start for someone else...
by toast0 - I feel like if you were gonna overthink this, you could’ve done something really cute and clever.
Like an AI that stares at the window and figures out which angle the sun is coming in, then makes a determination on what time it must be.
Then while it’s not sunny or can’t figure it out, it has dead reckoning, but it’s constantly looking at angles of shadows that determine if the time has drifted.
- It's not quite the same, but your prose clock solution reminded me of this: https://www.authorandco.com/products/author-clock.by dewarrn1
- 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.
by WillAdams - I'm with you. I like the DIY, take-things-into-own-hands drive and exploration. I think the next iteration would be nice as a back-to-basics learning journey, to see how less can be more, and explore the possible tools. (e.g. likely settling on a more elegant setup as you imply)
- I'm close to DIYing it also. I have two of the la crosse clocks. One works well. The other consistently fails to update. It would be cheaper to buy a new one to see if it's a dud or that location, but I already gave up on it and modified it to have a programmable LED strip integrated into it to visually indicate to my son when it was ok to get up for the day (before he could read a clock).
So, ironically, I've ended up with a non-automatic atomic clock that instead contains a raspberry pi pico w that speaks ntp and has a programmable LED strip. That I have to manually set every DST transition, although the LED controller handles it just fine.
by dgacmu - I’ve had a Phillips “atomic” alarm clock beside my bed for 23 years that just sets based on radio signal and auto restores if the power is lost, to which it has a backup 9v battery.
There’s a time zone setting offset slider and a DST slider. I basically touch it twice a year, maybe another if I move time zones. I’ve only had to touch it for DST (never switched time zones). Takes me conservatively 10 seconds to find and flip, so it’s taken me 460 seconds or a little under 8 minutes in the past 23 years to do time adjustments.
While these efforts are definitely fun hobby projects, there are cheap reliable solutions out there with minimal intervention that consume the NIST radio signal for time.
Just for anyone interested who wasn’t aware there’s some “old school” time broadcast solutions out there too besides NTP: https://www.nist.gov/pml/time-and-frequency-division/time-di...
by Frost1x - 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
by all2