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Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

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Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#151

Post by dang »

RupertSalt wrote: post #150
tanvach wrote: post #115

Related - we have an atomic Seiko wall clock expecting to have the time automatically adjusted by the WWVB LF atomic clock broadcast. Turns out, the signal is very weak where we now live. Manually setting the time on these atomic clocks is a HUGE pain (beware!). Turns out it's possible to emulate the atomic clock signal quite easily with a Raspberry Pi, or in my case I put together Arduino code that can emulate atomi…

You do not have an atomic clock. Seiko does not manufacture “Atomic Clocks” for the $30 shelf in Target. You (and others here) don’t seem to know what an atomic clock is, or how it works, or what it costs! Your Seiko is a radio clock. It’s probably got a crystal or some other normal timekeeping gadget, and the external WWV signal is decoded to properly set it. “Atomic Clocks” are marketed to ignorant consumers who bl…

Can you please make your substantive points without swipes? This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.

If you know more than someone else, that's great! By all means, share some of what you know, so the rest of us can learn. Just please do it without putdowns.

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#152

Post by pwg »

stavros wrote: post #142
ssl-3 wrote: post #65

Earlier quoted context omitted.

That's really neat. TIL. So the way this works seems to be this: It's an SRAM and an EEPROM in one little package along with a controller that talks with each, with a little capacitor (this clock uses 4.7uf) placed nearby. The SRAM part does all of the normal SRAM stuff: It doesn't wear out from reading/writing, and as long as it has power it retains the data it holds. The EEPROM does all the normal EEPROM stuff: It…

Has anyone found the chip on AliExpress? I only get unrelated listings with that part number, but this is a pretty interesting chip I'd like to get a few of. An alternative would be a supercapacitor and a voltage divider connected to the ADC pin of the microcontroller. When the 5V rail dies, the supercapacitor can hold 3.3V for a few seconds while you write everything to the EEPROM.

$0.77 US single piece cost on Digikey:

https://www.digikey.com/en/products/detail/microchip-technol...

And, at least with Digikey, you can feel like you actually get the real part vs. some low end clone knockoff.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#153

Post by ssl-3 »

vo2maxer wrote: post #141
ssl-3 wrote: post #137

Earlier quoted context omitted.

Yes, if we fucking choose to do that. We are.

Yes! The reflexive “must be LLM generated” is becoming ridiculous. Anything that includes proper punctuation and, god forbid, em dashes which I’ve used all my life must be suspect. The “it’s not x, it’s y” construction predates LLMs. I don’t recall ever sending a text without making sure it contained no errors, and yes, many have included infrequently used vocabulary.

I know, right?

I've been trying to write properly, clearly, and with the most expressive words I can come up with for many decades. I try to punctuate well, and to use functional formatting that I hope helps to effectively convey whatever it is that I'm on about. I try to improve as time goes on.

And I do this because if I'm going to bother with writing something for others to read, then I want my intended meaning to be easily-understood.

But increasingly, the instances where I manage to not screw any of that up too terribly result in a snarky and insulting retort in return.

And that kind of response is just not useful to anyone. I mean: What would people presume to have me do, instead? Become less-literate? Die in a fire? (Worse?)

fuh.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#154

Post by [deleted] »

ssl-3 wrote: post #92
bonsai_spool wrote: post #88

Earlier quoted context omitted.

What's the purpose of using an LLM to write a comment here?

"Hey, someone on the Internet used decent diction! Obviously, this means I must accuse them of being a bot!" (Hey Dang. Can we get a ban button? There's a few people here that are impossible to conduct rational discourse with. My sanity would improve if they were simply gone from my view.)

[deleted]

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#155

Post by BenjiWiebe »

KaiserPro wrote: post #94
ortichic wrote: post #37

Sorry if this is a dumb question, but do you guys not have radio controlled clocks outside of Europe? If I got it right, the only purpose of this project is to always display the correct time. Radio controlled clocks do exactly that. They are cheaper than the one ESP board, and run years on a single AA battery. No WiFi, tinkering, setup, or cables necessary

There is ( https://www.nist.gov/pml/time-and-frequency-division/time-se... ) and in some conditions you can receive the time signal in the UK. Our office manager bought some US tuned radio wall clocks, and every now and then they would jump 8 hours forward. I assume it was down to solar weather making propagation changes ( https://en.wikipedia.org/wiki/Sporadic_E_propagation )

Could easily be solar weather related propagation changes, but probably not Sporadic E specifically - that's much higher frequencies.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#156

Post by BenjiWiebe »

briHass wrote: post #134
teekert wrote: post #102

On this topic. Do WiFi signals contain time (unencrypted)? If so why does my oven not pull time from the air and needs adjustment every 2 months? If not, why are APs not defacto time beacons for all sorts of non-smart appliances (and clocks)?

The gateway/router should be the time source. DHCP has an option to provide the time server (NTP) - option 42, and most decent devices or OSS/DIY router software (OpenWRT, opnSense) will support that as well as being the local time server.

That does require being connected to the AP though.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#157

Post by vo2maxer »

ssl-3 wrote: post #153
vo2maxer wrote: post #141

Earlier quoted context omitted.

Yes! The reflexive “must be LLM generated” is becoming ridiculous. Anything that includes proper punctuation and, god forbid, em dashes which I’ve used all my life must be suspect. The “it’s not x, it’s y” construction predates LLMs. I don’t recall ever sending a text without making sure it contained no errors, and yes, many have included infrequently used vocabulary.

I know, right? I've been trying to write properly, clearly, and with the most expressive words I can come up with for many decades. I try to punctuate well, and to use functional formatting that I hope helps to effectively convey whatever it is that I'm on about. I try to improve as time goes on. And I do this because if I'm going to bother with writing something for others to read, then I want my intended meaning to…

It’s frustrating to the point that I have considered inserting grammatical errors, but that would go against my principles, which I have attempted to inculcate in my children. Yes, a significant amount of what’s posted is copied and pasted AI slop. But what in the world preceded this? Barely legible slop? I would much rather have someone craft their thoughts, run them through their preferred model, and write something coherent that is not marred by punctuation or basic elementary grammar errors. And you know what, the hell with the AI slop police. Yes, if we choose to use em dashes, we will.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#158

Post by ChuckMcM »

brokenmachine wrote: post #145
ChuckMcM wrote: post #75

Pretty awesome. The only thing I would change is to put a USB battery between the usb wall power and the D1 mini. That way for power outages of < a couple of days or so you're clock will be fine.

Why bother? Just get NTP time when the power comes back. It's syncing every 15 minutes anyway.

Because you want to know what time it is when the power is out?

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#159

Post by unsnap_biceps »

js2 wrote: post #114
Animats wrote: post #112

Earlier quoted context omitted.

Right. WWVB clocks running off the 60KHz pretty much solve the clock problem in the US. All my clocks at home are basic LaCrosse analog clocks. They have the internal sensors needed to tell when each hand is straight up, so they can set themselves without user input. On power up, they step until the hands are straight up, then sync when they get an update. You have to set the time zone with a switch when installing.…

> WWVB clocks running off the 60KHz pretty much solve the clock problem in the US. YMMV depending upon location. I've never gotten a WWVB clock to work in North Carolina. On the East Coast, the signal maybe sorta works for a few hours overnight: https://tf.nist.gov/tf-cgi/wwvbmonitor_e.cgi T̶h̶e̶y̶ ̶a̶l̶s̶o̶ ̶d̶o̶n̶'̶t̶ ̶t̶r̶a̶n̶s̶i̶t̶i̶o̶n̶ ̶D̶S̶T̶ ̶a̶u̶t̶o̶m̶a̶t̶i̶c̶a̶l̶l̶y̶,̶ ̶s̶o̶ ̶y̶o̶u̶'̶r̶e̶ ̶p̶u̶l̶l̶i̶n̶g̶ ̶t…

I have a few WWVB clocks. The ones that are on the north/south walls will never sync on their own, but east/west walls will sync just fine. I just take down the north/south clocks twice a year and lean them on a west facing wall and they'll sync overnight.

I think that most WWVB clocks just don't have the size to have an omni-directional antenna.

Re: Converting a $3.88 analog clock from Walmart into a ESP8266-based Wi-Fi clock

#160

Post by crote »

stavros wrote: post #138
ssl-3 wrote: post #72

Earlier quoted context omitted.

GPS isn't too hard, either. The receivers are inexpensive ($5-$10 for the kind of accuracy that's useful here) and it's not hard to parse the NMEA strings and PPS they output into a spooky-accurate internal clock. It only takes a few connections and an antenna to integrate GPS into an MCU like an ESP (or an SBC like a Raspberry Pi or a whatever). Like, really: The hardware is ridiculously easy. The only difficult par…

The actual difficult part is getting a GPS signal indoors with a cheap receiver, sadly.

The obvious answer is to use a Raspberry Pi as a GPS-disciplined NTP server, of course. Place it near the window or fully outside, depending on GPS signal strength.

That gives you another weekend project, and you can reuse your DIY NTP wall clock!

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