Never Go To The Office Breakroom Again

If you’re tired of having to make small talk with random people in the office break room every time you need a cup of coffee, or simply don’t have the time to get up to pour yourself some more, it would be nice if there was a way you could have your cup filled for you, right at your desk. With this new drink dispenser, you won’t have to get up or even pour your drinks yourself!

We’ve certainly seen plenty of automatic drink makers, but those are more suited to parties and complicated drink mixing. This beverage dispenser is more for the person who knows their tastes and simply wants to save some time. It’s also much simpler, using a peristaltic pump for serving a single liquid from a large bottle into a glass, and using a load cell to know when to stop filling. The peristaltic pump is a little slow though, so it’s best to set the glass back in the dispenser and let it top you off each time.

We’re a big fan of time savers around here, especially when it comes to improving workflow. Of course, the best time saver is a clean, well-organized shop which will help you out whether you’re building a drink dispenser or anything else.

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A Tinfoil-Free Internet Of Ceiling Fans

Putting everything on the Internet is getting easier and easier, what with the profusion of Internet-ready appliances as well as cheap and plentiful IoT modules to integrate legacy devices. Think IoT light bulbs, refrigerators and dishwashers that can be controlled from a smartphone, and the ubiquitous Sonoff modules. But once these things are on the net, what are they talking about? Are they saying things behind your back? Are they shipping data about your fridge contents off to some foreign land, to be monetized against your will?

Maybe, maybe not, but short of a tinfoil helmet the only way to protect yourself is to build your own system. This IoT control for ceiling fans is a good example, with the added benefit that most wireless ceiling fan remotes are kind of lousy. [microentropie] didn’t like the idea of going the Sonoff route, so his custom controller is based on that IoT workhorse, the ESP8266. There are two versions, one switching the light and fan loads with relays, and one with triacs. The ESP serves up its own web page for control rather than using a cloud service, and is capable of setting up the fan to turn on and off automatically at preset times or temperatures. Everything sits in an unobtrusive box on the ceiling near the fan, but we bet this could be miniaturized enough to fit right inside the fan housing.

If some of [microentropie]’s code looks familiar, it might be because he borrowed it from his IoT rice cooker project.

The Tourbillon: Anti-Gravity for Watch Movements

Do you know what time it is? Chances are good that you used a computer or a cell phone to answer that question. The time on your phone is about as accurate as chronometry gets these days. That’s because cell networks are timed from satellites, which are in turn timed from atomic clocks. And these days, it may be that atomic clocks are the only clocks that matter.

Before this modern era of quartz and atomic accuracy, though, timepieces were mechanical. Clocks were driven by heavy weights that made them impractical for travel. It wasn’t until the mainspring-driven movement came along that timekeeping could even begin to become portable.

But while the invention of the mainspring made portable timepieces possible, it hurt their accuracy. That’s because the driving force of a tightly wound spring isn’t constant like that of an inert, solid weight.  So pocket watches weren’t exactly an overnight success. Early pieces were largely ornamental, and only told the hour. Worst of all, they would slow down throughout the day as the mainspring unwound, becoming useless unless wound several times a day. The mainspring wasn’t the only problem plaguing pocket watches, but it was the among the most obvious.

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Get Inside a TCXO Clock Chip

[Pete] wondered how real-time clock modules could be selling on eBay for $1.50 when the main component, the Maxim DS3231 RTC/TCXO chip, cost him more like $4 apiece. Could the cheap modules contain counterfeit chips?

Well, sure they could. But in this case, they didn’t, and [Pete] has the die shots to prove it. He started off by clipping the SOIC leads rather than desoldering — he’s not going to be reusing this chip after he’s cut it in half. Next was a stage of embrittling the case by heating it up with a lighter and dunking it in water. Then he went at it with sandpaper.

It’s cool. You can see the watch crystal inside, and all of the circuitry. The DS3231 includes a TCXO — temperature-corrected crystal oscillator — and it seems to have a bank of capacitors that it connects and disconnects depending on the chip’s temperature to keep the oscillator running at the right speed. [Pete] used one in an offline situation, and it only lost sixteen seconds over a year, so we’d say that they work fine.

If you’d like to know more about how crystals are used to keep time, check out [Jenny]’s excellent article. And if sixteen second per year is way too much for you, tune up your rubidium standard and welcome to the world of the time nuts.

One Micro Bit Accomplishes Its Goal

Like the Raspberry Pi, the BBC Micro Bit had a goal of being foremost an educational device. Such an inexpensive computer works well with the current trend of cutting public school budgets wherever possible while still being able to get kids interested in coding and computers in general. While both computers have been co-opted by hackers for all kinds of projects (the Pi especially), [David]’s latest build keeps at least his grandkids interested in computers by using the Micro Bit to add some cool features to an old toy.

The toy in question is an old Scalextric slot car racetrack – another well-known product of the UK. But what fun is a race if you can’t keep track of laps or lap times? With the BBC Mirco Bit and some hardware, the new-and-improved racetrack can do all of these things. It also implements a drag race-style light system to start the race and can tell if a car false starts. It may be a little difficult to intuit all of the information that the Micro Bit is displaying on its LED array, but it shouldn’t take too much practice.

The project page goes into great detail on how the project was constructed. Be sure to check out the video below for some exciting races! The build is certain to entertain [David]’s grandkids for some time, as well as help them get involved with programming and building anything that they can imagine. Maybe they’ll even get around to building a robot or two.

Thanks to [Mark] for sending in this tip!

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Micro Radio Time Station Keeps Watch in Sync

The US National Institute of Standards and Technology (NIST) broadcasts atomic clock time signals from Fort Collins, Colorado on various frequencies. The WWVB signal on 60 kHz blasts out 70,000 watts that theoretically should reach the entire continental US. Unfortunately for [Anish Athalye], the signals do not reach his Massachusetts dorm, so he built this GPS to WWVB converter to keep his Casio G-Shock self-setting watch on track.

Not a repeater but a micro-WWVB transmitter, [Anish]’s build consists of a GPS receiver module and an ultra low-power 60kHz transmitter based on an ATtiny44a microcontroller’s hardware PWM driving a ferrite rod antenna. It’s not much of a transmitter, but it doesn’t need to be since the watch is only a few inches away. That also serves to keep the build in compliance with FCC regulations regarding low-power transmissions. Heavy wizardry is invoked by the software needed to pull time data off the GPS module and convert it to WWVB time code format, with the necessary time zone and Daylight Savings Time corrections. Housed in an attractive case, the watch stand takes about three minutes to sync the watch every night.

[Anish] offers some ideas for improving the accuracy, but we think he did just fine with this build. We covered a WWVB signal spoofer before, but this build is far more polished and practical.

Set Your Clocks to Decimal Time

Many stop lights at street intersections display a countdown of the remaining seconds before the light changes. If you’re like me, you count this time in your head and then check how in sync you are. But did you know that if the French had their way back in the 1890s when they tried to introduce decimal time, you’d be counting to a different beat? Did you know the Chinese have used decimal time for millennia? And did you know that you may have unknowingly used it already if you’ve programmed in Linux? Read on to see what decimal time is along with the answers to these questions.

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