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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

#191

Post by aidenn0 »

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…

The loopstick antennas used in many inexpensive WWVB receivers have a fairly strong null, so rotating the clock 90 degress can make reception possible.

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

#192

Post by aidenn0 »

montroser wrote: post #55

What I really want is one of these powered by gps. The time already comes for free in the signal, and from your location you can derive the time zone. That way DST is accounted for automatically, but you don't have to set up and rely on wifi. This would be truly zero-config and always correct.

I strongly suspect that GPS time reception is going to use far more battery power than polling NTP.

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

#193

Post by aidenn0 »

sowbug wrote: post #18
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.

I remember clocks in my school would sync up by all running forward to 12 at noon (and presumably midnight). I don't know if it was a radio or wired signal.

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

#194

Post by ComputerGuru »

BenjiWiebe wrote: post #156
briHass wrote: post #134

Earlier quoted context omitted.

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.

The counterpoint to that is you aren't trusting any random wifi signal strong enough to reach your device to be telling the truth about the time!

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

#195

Post by ssl-3 »

butvacuum wrote: post #175
stavros wrote: post #169

Earlier quoted context omitted.

Comes out to $6 per part for me, with shipping, which is much more than I'm willing to pay.

and it'd still be $6 for 600. It's as if people have never had shipping itemized before. The only reason aliexpress shopping is cheap is because the rest of the world foots the bill. Unless somebody has finally removed China's "Developing Country" status thats gotten them essentially free international parcel service for the best part of 100 years.

Have you looked lately?

I buy small parts with "Choice" shipping on AliExpress sometimes, because it's cheap and [usually] quick and they take care of all of that pesky tariff and customs business in ways that never have an opportunity to surprise me.

For years now, the shipping process has worked like this for me: They gather it up on their end and send the stuff on a cargo plane to a sort that is at or near JFK airport in New York.

If the order includes things from several different sellers, then at some point they generally get combined into one bag.

From there, they just mail it -- using regular, domestic USPS service. It shows up in my mailbox on my porch in Ohio a few days later.

Although it certainly was a thing I've experienced in the past, at no point does the process I've described exploit the "Developing County" loophole. They just send things to the other side of the world (at their expense), and then pay the post office the same way as anyone else does to bring it to my door.

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

#196

Post by [deleted] »

abustamam wrote: post #179
Dachande663 wrote: post #104

Earlier quoted context omitted.

Upvoted because this stinks to high hell of an LLM response. Half the GPs comments seem to be in a similar vein. It’s such a shame but you can’t fight the trolls so don’t take it to heart.

Whether or not they did use an LLM to refine, what does it matter? To call them a troll for contributing to discourse is wild.

[deleted]

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

#197

Post by VladVladikoff »

bArray wrote: post #182
VladVladikoff wrote: post #178

I don’t understand why it needs to neurotically check so frequently? 30 times a second seems like a lot of hammering on the NTP server. Am I missing something here? Some physical reason why that is necessary perhaps?

> The ESP8266 reconnects to the NTP server every 15 minutes which keeps the clock accurate. It doesn't seem to be hammering the NTP server 30 times a second.

Ah ok, I guess I misunderstood this part:

>Ten times each second the ESP8266 compares the time displayed on the analog clock to the actual time retrieved from an NTP server.

Not sure where I got 30 from. Dyslexia between reading and commenting.

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

#198

Post by stevenjgarner »

BeeOnRope wrote: post #140
stevenjgarner wrote: post #122

$3.88 ? Walmart.com uses dynamically variable pricing that includes geographic and user variance - my price is $5.92 https://www.walmart.com/ip/Mainstays-Basic-Indoor-8-78-Black...

User variance? Any evidence?

While Walmart has historically denied using "individualized" pricing (charging two people different prices for the exact same item based on their income), they do use behavioral targeting [1]

Members of Walmart+ often see different "final" prices due to exclusive discounts, rewards (Walmart Rewards), or waived shipping/delivery fees that aren't available to guest users. Walmart uses AI to offer personalized promotions. You might see a "Rollback" or a "Just for You" offer on an item you’ve viewed multiple times or purchased previously, effectively changing the price for you specifically via a targeted discount. Like many e-commerce giants, Walmart may also offer "first-time app user" discounts or "win-back" coupons to specific customer segments.

[1] https://goaura.com/blog/walmart-pricing-strategies

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

#199

Post by bArray »

VladVladikoff wrote: post #197
bArray wrote: post #182

Earlier quoted context omitted.

> The ESP8266 reconnects to the NTP server every 15 minutes which keeps the clock accurate. It doesn't seem to be hammering the NTP server 30 times a second.

Ah ok, I guess I misunderstood this part: >Ten times each second the ESP8266 compares the time displayed on the analog clock to the actual time retrieved from an NTP server. Not sure where I got 30 from. Dyslexia between reading and commenting.

No worries. You would be right to be concerned about an NTP server being polled so regularly.

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

#200

Post by butvacuum »

ssl-3 wrote: post #195
butvacuum wrote: post #175

Earlier quoted context omitted.

and it'd still be $6 for 600. It's as if people have never had shipping itemized before. The only reason aliexpress shopping is cheap is because the rest of the world foots the bill. Unless somebody has finally removed China's "Developing Country" status thats gotten them essentially free international parcel service for the best part of 100 years.

Have you looked lately? I buy small parts with "Choice" shipping on AliExpress sometimes, because it's cheap and [usually] quick and they take care of all of that pesky tariff and customs business in ways that never have an opportunity to surprise me. For years now, the shipping process has worked like this for me: They gather it up on their end and send the stuff on a cargo plane to a sort that is at or near JFK air…

EDIT: Oh lord, bad typo in my previous comment- it should have been aliexpress SHIPPING not Shopping.

It's not the same, what you described is Direct Entry (somewhere around page 25, linked below). Apparently the Terminal Dues system has been massively changed in the 5 years since I last looked- but it still appears unfavorable to USPS and US sellers, while favoring high volume foreign shippers.

https://www.gao.gov/assets/gao-18-112.pdf

As for how aliexpress delivers stuff, since the tarrifs: 1) no-name last mile. 2) USPS last mile, and USPS the entire way.

I don't know if any are associated with "Choice", Paid store shipping, and/or free store shipping.

Since I normally buy from aliexpress to avoid the insane 200-800% markups amazon/ebay/walmart/etc dropshippers demand the $5-$10 in shipping doesnt factor in.

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