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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

#11

Post by relaxing »

kotaKat wrote: post #2

Of note, having recently shopped at Walmart for a self-setting alarm clock (what I once knew to be “atomic”): Apparently the entity today known as Sharp sells “AccuSet(tm)” branded clocks that “automatically set time”… but they’re just factory pre-set with a button cell and they include a slider on the bottom to set a timezone offset (only for US timezones). If you’re lucky, the clock’s battery is still good and the…

You want a self-setting radio clock that receives the LF broadcast from WWVB.

There was a kerfuffle a few years back about the funding for the station being cut, but luckily that did not come to be.

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

#12

Post by orev »

kotaKat wrote: post #2

Of note, having recently shopped at Walmart for a self-setting alarm clock (what I once knew to be “atomic”): Apparently the entity today known as Sharp sells “AccuSet(tm)” branded clocks that “automatically set time”… but they’re just factory pre-set with a button cell and they include a slider on the bottom to set a timezone offset (only for US timezones). If you’re lucky, the clock’s battery is still good and the…

These clocks are irritating because they show up in the results when searching for “radio atomic clock” and similar, and it can be very hard to figure out if they actually use the WWVB radio signal. I’ve concluded that none of them do, because WWVB is only reliable in (most parts) of the US, and companies only want to make things that appeal to a global audience now. La Crosse seems to be the only one that makes them, and unfortunately most of their designs lack any style (i.e. they’re ugly).

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

#13

Post by riskable »

I want to see someone convert one of those cheap projection clocks like this: https://www.homedepot.com/p/La-Crosse-Technology-5-in-Color-...

The red projection is just the right brightness (at night) but it sucks that it's not wifi-enabled so you can't just get it to NTP sync (or hook up a GPS receiver). The projector part of the clock is a separate device that's attached to it via a ribbon cable. I would reverse engineer it myself but I haven't got the time.

Ideally, I'd want a matrix of LEDs projected on to the ceiling so I could get more info than just the time. Such clocks exist but they're super duper expensive! Example: https://buyfrixos.com/

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

#14

Post by avidiax »

How does this keep track with DST?

Looking at the code [1], it looks like if the actual time is 1 hour ahead of the displayed time, then we get 10 pulses per second to leap forward. Otherwise, the clock stops running for an hour to fall back.

https://github.com/jim11662418/ESP8266_WiFi_Analog_Clock/blo...

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

#15

Post by sowbug »

DesiLurker wrote: post #3

makes me wonder what if I just wanted to sync with nfc every once in a while. wifi seems overkill for this. maybe it could be done much cheaper with nfc sync witha phone twice a year?

We've been shopping for a simple bathroom clock to replace our final Amazon Echo and leave that increasingly dystopian ecosystem. There are some models that use Bluetooth on your phone to sync the time. I could imagine BLE being a good low-power and relatively stateless solution. But given our goals, we're not going to install an app on a phone just to maintain a wall clock. (I'd be fine if Android provided BLE time sync as a built-in service.)

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

#18

Post by sowbug »

avidiax wrote: post #14

How does this keep track with DST? Looking at the code [1], it looks like if the actual time is 1 hour ahead of the displayed time, then we get 10 pulses per second to leap forward. Otherwise, the clock stops running for an hour to fall back. https://github.com/jim11662418/ESP8266_WiFi_Analog_Clock/blo...

You have two choices: either assume everyone is asleep at 2 am and won't notice when it happens, or else advance 11 hours. My LaCrosse clock does the latter.

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

#19

Post by gspr »

avidiax wrote: post #14

How does this keep track with DST? Looking at the code [1], it looks like if the actual time is 1 hour ahead of the displayed time, then we get 10 pulses per second to leap forward. Otherwise, the clock stops running for an hour to fall back. https://github.com/jim11662418/ESP8266_WiFi_Analog_Clock/blo...

And that's pretty much fine for a project like this, seeing as most (all?) locations jump you between DST and not DST at night. So the clock will be off at most for an hour during the night.

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

#20

Post by lostlogin »

riskable wrote: post #13

I want to see someone convert one of those cheap projection clocks like this: https://www.homedepot.com/p/La-Crosse-Technology-5-in-Color-... The red projection is just the right brightness (at night) but it sucks that it's not wifi-enabled so you can't just get it to NTP sync (or hook up a GPS receiver). The projector part of the clock is a separate device that's attached to it via a ribbon cable. I would reverse en…

Undermining the spirit of HN: By the time you’ve spent a few hours hacking away and bought any parts, that price is probably not too bad.
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