IoT

325 Articles

If It Ain’t Broke… Add Something To It

November 15, 2025 by 10 Comments

Given that we live in the proverbial glass house, we can’t throw stones at [ellis.codes] for modifying a perfectly fine Vornado fan. He’d picked that fan in the first place because, unlike most fans, it had a DC motor. Of course, DC motors are easier to control with a microcontroller, and next thing you know, it was sporting an ESP32 and a WiFi interface.

The original fan was surprisingly sparse inside. A power supply, of course, and just a tiny PCB for a speed control. Oddly, it looks like the speed control was just a potentiometer and a 24 V supply. It wasn’t clear if the “motor” had some circuitry in it to do PWM control or not. That seems likely, though.

Regardless, the project opted for a digital pot IC to maintain compatibility. One nice thing about the modification is that it replaces the existing board with the same connectors. So if you wanted to revert the fan to normal, you simply have to swap the boards back.

Now the fan talks to home automation software. Luckily, there’s still nothing wrong with it. We love seeing bespoke ESPHome projects. Even if your fan has WiFi, you might not like it communicating with Big Brother.

splashflag iot swimming notification

Splashflag: Raising The Flag On A Pool Party

October 5, 2025 by 7 Comments

Some things are more fun when there are more folks involved, and enjoying time in the pool is one of those activities. Knowing this, [Bert Wagner] started thinking of ways to best coordinate pool activities with his kids and their neighborhood friends. Out of this came the Splashflag, an IoT device built from the ground up that provides fun pool parties and a great learning experience along the way.

The USB-powered Splashflag is housed in a 3D-printed case, with a simple 2×16 LCD mounted on the front to display the notification. There’s also a small servo mounted to the rear that raises a 3D-printed flag when the notification comes in—drawing your attention to it a bit more than just text alone would. Hidden on the back is also a reset button: a long press factory-resets the device to connect to a different Wi-Fi network, and a quick press clears the notification to return the device to its resting state.

Inside is an ESP32-S3 that drives the servo and display and connects to the Wi-Fi. The ESP32 is set up with a captive portal, easing the device’s connection to a wireless network. The ESP32, once connected, joins an MQTT broker hosted by [Bert Wagner], allowing easy sending of notifications via the web app he made to quickly and easily send out invitations.

Thanks, [Bert Wagner], for sharing the process of building this fun, unique IoT device—be sure to read all the details on his website or check out the code and design files available over on his GitHub. Check out some of our other IoT projects if this project has you interested in making your own.

Continue reading “Splashflag: Raising The Flag On A Pool Party” →

Walter Is A Tiny Cellular Modem For Your Projects

August 16, 2025 by 21 Comments

It wasn’t that long ago that projects with cellular connectivity were everywhere, but with 2G no longer universally available, glory days of cheap 2G modules seem to be on their way out. So when [Data Slayer] titled his video “You’ve Never Seen Cellular Like This” about a new GSM radio module, we couldn’t help but think that we have — and that we’re glad to see it back.

The module is the Walter, by DPTechnics out of Belgium. It’s fully open-source and contains a ESP32-S3 for WiFi and BLE plus a Sequans Monarch chip for GSM and GNSS connectivity. It’s not the blazing-fast 5G you’re paying your phone carrier for: this is an IoT modem, with LTE-M and NB-IoT. We’re talking speeds in the kbps, not Mbps– but we’re also talking very, very low power usage. Since it’s LTE-M rather than full LTE, you’re probably not going to be bringing back the golden days of Arduino Cellphones,  (since LTE-M doesn’t support VoLTE) but if LoRa isn’t your jam, and you hang out around cell towers, this level of connectivity might interest you.

Walter is actually a drop-in replacement for PyCom’s old GPy module, so if you had a project in mind for that and are frustrated by it being EoL — well, here you are. [Data Slayer] seemed impressed enough with its capabilities as a GPS tracker. We’re impressed with the 9.8 µA consumed in deep sleep mode, and the fact that it has already been certified with the CE, FCC, IC, RCM and UKCA. Those certs mean you could go from prototype to product without getting tangled in red tape, assuming Walter is the only radio onboard.

Our thanks to [Keith Olson] for phoning in the tip. If you have a tip and want to connect, operators are standing by. Continue reading “Walter Is A Tiny Cellular Modem For Your Projects” →

BhangmeterV2 Answers The Question “Has A Nuke Gone Off?”

June 18, 2025 by 47 Comments

You might think that a nuclear explosion is not something you need a detector for, but clearly not everyone agrees. [Bigcrimping] has not only built one, the BhangmeterV2, but he has its output publicly posted at hasanukegoneoff.com, in case you can’t go through your day without checking if someone has nuked Wiltshire.

The Bhangmeter is based on an off-the-shelf “nuclear event detector”, the HSN-1000L by Power Device Corporation.