Keeping An Eye On The Water Heater Pilot Light

[WJCarpenter]’s gas water heater uses a small pilot light that needs to stay burning permanently to ignite the main burners as required. Four or five times a year, the pilot light goes out and needs to be manually lit. This involves an expedition from the upstairs bathroom to the basement, always in the early morning, after having spent a few fruitless minutes waiting for hot water. Having grown tired of this exercise, [WJCarpenter] built Water Watcher, a pilot light monitoring system with some ESPs and a light sensor.

Water Watcher consists of an ESP8266 connected to a light sensor taped to the inspection window of the water heater. It reports the status of the pilot light over MQTT to an ESP32-based M5 Atom Matrix in the main bedroom, which displays it using a 5×5 RGB matrix, as demonstrated after the break. Both ESPs run ESPHome, so programming is as easy as giving it a YAML config file. [WJCarpenter] tested a few different light sensors, until he found the TSL2591, which is sensitive to the right wavelengths and has enough dynamic range for watching a pilot light.

This might not be a complicated hack, but we do not doubt that it reduces frustration a bit on those fateful mornings. Be sure to check out the Water Watcher project page, it’s an entertaining read! Continue reading “Keeping An Eye On The Water Heater Pilot Light”

Dynamic Map Of Italy On A PCB

While most PCBs stick to tried-and-true methods of passing electrons through their layers of carefully-etched copper, modern construction methods allow for a large degree of customization of most aspects of these boards. From solder mask to number of layers, and even the shape of the board itself, everything is open for artistic license and experimentation now. [Luca] shows off some of these features with his PCB which acts as a live map of Italy.

The PCB is cut out in the shape of the famous boot, with an LED strategically placed in each of 20 regions in the country. This turns the PCB into a map with the RGB LEDs having the ability to be programmed to show any data that one might want. It’s powered by a Wemos D1 Mini (based on an ESP8266) which makes programming it straightforward. [Luca] has some sample programs which fetch live data from various sources, with it currently gathering daily COVID infection rates reported for each of the 20 regions.

The ability to turn a seemingly boring way to easily attach electronic parts together into a work of art without needing too much specialized equipment is a fantastic development in PCBs. We’ve seen them turned into full-color art installations with all the mask colors available, too, so the possibilities for interesting-looking (as well as interesting-behaving) circuits are really opening up.

Continue reading “Dynamic Map Of Italy On A PCB”

ESP8266 Socket Is A Snap-Fit, Breadboard-Friendly Wonder

It all started with wanting to program an ESP-12 variant of an ESP8266 module without involving any solder. Displeased with all the socket offerings on Thingiverse, [tweeto] set out to design their own breadboard-friendly snap-fit socket.

This certainly looks like a handy solution. All you have to do is print the thing, add all the wires, and stick your ESP in there. Even that wire is easy to find; [tweeto] used 0.8 mm paper clips which are sturdy, conductive, and haunting the darkest corners of every desk drawer. They’re also a little bit on the thick side, so [tweeto] plans to test out 0.6mm copper wire in the future.

The challenge with this type of print is to design something that will stand up to repeated breadboardings without losing legs or falling apart. [tweeto]’s elegant solution is a tiny groove for each wire in the bottom of the socket — it keeps the wire in place by countering the play caused by inserting it into and removing it from a breadboard. See how [tweeto] bends the paper clips in the short video after the break.

There’s more than one way to use 3D printing to your circuit-building advantage, even in permanent circuits — just take a look at this PCB-free Arduboy.

Continue reading “ESP8266 Socket Is A Snap-Fit, Breadboard-Friendly Wonder”

Automating Your Car With A Spare Fob And An ESP8266

Despite the name, home automation doesn’t have to be limited to only the devices within your home. Bringing your car into the mix can open up some very interesting possibilities, such as automatically getting it warmed up in the morning if the outside air temperature drops below a certain point. The only problem is, not everyone is willing to start hacking their ride’s wiring to do it.

Which is exactly why [Matt Frost] went the non-invasive route. By wiring up an ESP8266 to a cheap aftermarket key fob for his Chevrolet Suburban, he’s now able to wirelessly control the door locks and start the engine without having to make any modifications to the vehicle. He was lucky that the Chevy allowed him to program his own fob, but even if you have to spend the money on getting a new remote from the dealer, it’s sure to be cheaper than the repair bill should you cook something under the dash with an errant splice or a misplaced line of code.

The hardware for this project is about as simple as it gets. The fob is powered by the 3.3 V pin on the Wemos D1 Mini, and the traces for the buttons have been hooked up to the GPIO pins. By putting both boards into a custom 3D printed enclosure, [Matt] came up with a tidy little box that he could mount in his garage and run off of a standard USB power supply.

On the software side of things [Matt] has the device emulating a smart light so it can easily be controlled by his Alexa, with a few helpful routines sprinkled in that allow him to avoid the awkward phraseology that would be required otherwise. There’s also a minimal web server running on the microcontroller that lets him trigger various actions just by hitting the appropriate URLs, which made connecting it to Home Assistant a snap. One downside of this approach is that there’s no acknowledgement from the vehicle that the command was actually received, but you can always send a command multiple times to be sure.

This isn’t the first time we’ve seen an ESP8266 used to “push” buttons on a remote. If you’ve got a spare fob for your device, or can get one, it’s an excellent way to automate it on the cheap.

PIR Sensor In A Jar Helps You Keep Your Concentration

While there are loads of impressive and complex projects here on Hackaday, sometimes it’s the simple ones that really speak to us. In this case we were presented with [Isabell Park]’s easy-to-follow instructable on how to build an anti-procrastination device.

On the hardware side there are no surprises, it consists of a PIR sensor connected to a NodeMCU microcontroller. It checks for a signal from the sensor, and if it’s triggered, it sends a command through the Adafruit IO libraries to IFTTT. On its own it could make for a decent movement alarm, but the part that makes the project interesting is how it’s applied to become a device to help with procrastination instead.

First, you put your phone in a jar along with the electronics and close it. Then, with everything configured, the circuit is powered on and stays vigilant for any movement inside the jar. Should you try to take your phone out of it for a quick social media break (which, if you’re like us, can turn into a few hours), IFTTT will be alerted and run through whatever script you have in place. In [Isabell]’s case, she suggests sending an SMS to a trusted contact to keep you in check.

If you’re looking to keep track of how much time you’ve spent procrastinating, have we got a clock for you. But if you’re looking for more projects involving PIR sensors, we have one that alerts you when your cat is back home. Meanwhile, check out this one in action after the break. Continue reading “PIR Sensor In A Jar Helps You Keep Your Concentration”

A Tiny LED Matrix Is Better With Friends

When we last heard from [lixielabs] he was building Nixie tube replacements out of etched acrylic and LEDs. Well he’s moved forward a few decades to bring us the Pixie, a chainable, addressable backpack for tiny LED matrix displays.

Each Pixie module is designed to host two gorgeous little Lite-On LTP-305G/HR 5×7 LED dot matrix displays, which we suspect have been impulse purchases in many a shopping cart. Along with the displays there is a small matrix controller and an ATTINY45 to expose a friendly electrical interface. Each module is designed to be mounted edge to edge and daisy chained out to 12 or more (with two displays each) for a flexible display any size you need. But to address the entire array only two control pins are required (data and clock).

[lixielabs] has done the legwork to make using those pins as easy as possible. He is careful to point out the importance of a good SDK and provides handy Arduino libraries for common microcontrollers and a reference implementation for the Raspberry Pi that should be easy to crib from to support new platforms. To go with that library support is superb documentation in the form of a datasheet (complete with dimensions and schematic!) and well stocked GitHub repo with examples and more.

To get a sense of their graphical capabilities, check out a video of 6 Pixie’s acting as a VU meter after the break. The Pixie looks like what you get when a hacker gets frustrated at reinventing LED dot matrix control for every project and decided to solve it once and for all. The design is clean, well documented, and extremely functional. We’re excited to see what comes next! Continue reading “A Tiny LED Matrix Is Better With Friends”

Roll Your Own Tracking

The smartphone is perhaps the signature device of our modern lives. For most of the population it is never more than an arm’s length away, it’s on your person more than any other device in your life. Smartphones are packed with all sorts of radios and ways to communicate wireless. [Amine Mansouri] built an ESP8266 based tracking device that takes advantage of this.

Most WiFi-enabled devices will send out “probe requests” frames trying to search for the SSIDs they were connected to. These packets contain the device MAC address as well as the SSIDs you’ve connected to. Using about 12 components, [Amine] laid out a small board in Eagle. By putting the ESP8266 in monitor mode, the probe frames can be logged and uploaded. The code can be updated OTA making it easy to service while in the field.

With permission from his local library, eight repeater boards were scattered throughout the building to forward the probe packets to where the tracker could pick them up. A simple web interface was built that allows the library to figure out how many people are in the library and how often they frequent the premises.

While an awesome project with open-source code on Github, it is important to stress how important is it to get permission to do this kind of tracking. While some phones implement MAC randomization, there are still many out in the wild that don’t. While this is similar to another project that listens to radio signals to determine the coming and going of ships and planes, tracking people with this sort of granularity is in a different category altogether.

Thanks [Amine] for sending this one in!