LoRa

117 Articles

FCC ISM Rules May Shatter Lora Mesh Communities

September 17, 2026 by 128 Comments

Although everyone has their own reasons for exploring a new hobby, one of the driving factors behind the popularity of Meshtastic and MeshCore has been the incredible accessibility offered by off-grid LoRa mesh networks. You don’t need any expensive hardware or a license to get on the air — armed with a $20 microcontroller dev board and open source software, you could be on the mesh in minutes. Then came the really exciting part, seeing who else was out there. The low barrier of entry and ad-hoc nature of these projects meant there was a good chance you’d soon find yourself exchanging messages with other like-minded folks in the area.

Or at least, that’s how it used to be. With the recent revelation that their default radio configurations have potentially been in violation of the Federal Communications Commission’s (FCC) regulations governing amateur usage of the 900 MHz industrial, scientific and medical (ISM) band, the users and developers of both Meshtastic and MeshCore have been sent scrambling. Getting in compliance isn’t necessarily a technical challenge. In fact, Meshtastic has already introduced changes aimed to address the issue and anyone running the latest alpha release can be sure that their initial radio configuration will meet FCC standards.

But unfortunately, this introduces a new problem. While it’s easy enough to get new installations of Meshtastic and MeshCore operating in a mode that keeps the FCC happy, doing so breaks compatibility with everything that’s already been deployed. The community will be fractured into distinct strata depending on when they first configured their hardware, with an added dash of confusion from the more rebellious users who will undoubtedly refuse to migrate over to the new settings.

What was once easy and accessible has just gotten a whole lot more complicated.

Continue reading “FCC ISM Rules May Shatter Lora Mesh Communities” →

A man's hand is shown holding two small circuit boards, joined together by a central bridge. Each circuit board is connected to four wires and a coaxial antenna cable.

Open-Source ExpressLRS Receiver Reaches For Range

August 22, 2026 by 33 Comments

Drone control links are, from a radio signals perspective, nothing short of amazing: using a transmitter capable of transmitting, at most, one watt, a protocol such as ExpressLRS (ELRS) can control a drone over 100 kilometers away. [Stan], who has been building a drone electronics stack from scratch, recently designed four ELRS receivers and went over the principles behind their incredible range.

Up to a certain point, the simplest way to increase a radio’s range is to lower the frequency; lower radio frequencies penetrate better through most materials and don’t attenuate as quickly with distance. However, although ELRS can use 900 MHz bands, [Stan]’s receivers primarily use 2.4 GHz. The major improvement is in modulation: unlike other control protocols, which mostly use frequency modulation, or Wi-Fi, which uses phase and amplitude modulation, ELRS uses Chirp Spread Spectrum modulation. This has a low data rate, but it’s very reliable; every bit is transmitted as a chirp – a linearly rising radio tone – and the data is encoded in the chirp’s starting frequency. To decode this, the receiver multiplies it with an inverse chirp, then takes a fast Fourier transform, revealing the starting frequency. This process has an equivalent gain of 24 dB, which is enough to let it decode signals even below the receiver’s noise floor.

The hardware [Stan] designed to implement this was comparatively simple, just an ESP32 microcontroller, an SX1281 radio chip, and a few peripherals. All four receivers worked in 2.4 GHz, but two had additional 900 MHz antennas. Against RF design convention, one of the receivers used a via to connect the antenna. This would normally cause a significant impedance mismatch, but since there were enough ground-plane vias nearby, the current return path was barely affected; the receiver’s performance hardly changed. In one test, all four receivers maintained a connection at more than five kilometers, despite a forest blocking the signal’s path.

We previously covered ExpressLRS when it was still an emerging technology. To get this kind of range, it builds on LoRa technology, which has reached some impressive distance records.

Thanks to [Keith Olson] for the tip!

Store Tunes On Paper And Stream Them Over LoRA

August 18, 2026 by 37 Comments

Some projects seem too good to be true until you dig into it and find the secret magic that makes it all work. Take Paper Tunes by [Makestreame], a project which purports to store a song on a single sheet of paper via QR code and transmit the data over LoRA. If it was a MIDI sequence, maybe. But the promise of Paper Tunes is to take any MP3 and give it this treatment, and that just seems like an impossible level of compression at first glance.

The music is heavily compressed, make no doubt about that. There’s samples in the Instructables link above and in the video below, but it sounds far better than it has any right to. The secret is Meta’s EnCodec neural codec, which like you’d guess uses neural nets to squeeze the absolute minimum information needed to reconstruct a sample. With it [Makestreame] is able to get a 2.9 MB MP3 file down to just 21.44 kB.

Of course, that’s still not going to fit in a 3.3 kB QR code. But by simply making eight of them, [Makestreame] is able to fit the song onto the front and back of a piece of paper. Yes, each song has an “A” and a “B” side — and you thought flipping a record halfway through got old fast. Having to scan eight codes to get one song may strike some as a bit silly, but we do enjoy some silly things here.

The same EnCodec compression that gets the song so tiny as to fit in a brace of QR codes is obviously also what enables its transmission over LoRA. While it’s got far lower bandwidth than something like WiFi, 21 kB is well within its limits. It’s often said that LoRA isn’t suitable for audio, but this project is another example that one person’s “unsuitable” is another person’s “challenge accepted”.

We’ve seen other LoRA audio projects before. Speaking of things not suitable for audio, we once featured an entire album crammed onto a floppy disk. Continue reading “Store Tunes On Paper And Stream Them Over LoRA” →

The Hackaday Communicator Badge, Re-Imagined With New Firmware

June 12, 2026 by 20 Comments

Our recently concluded event in Europe saw the return of the Hackaday Communicator badge — a stylish handheld gadget with a QWERTY keyboard, a LoRa radio, and an ESP32. It came complete with a simple messaging app built into its MicroPython firmware, and by all accounts it was a great success.

But there was certainly room for improvement, which is where [Giovi321]’s new firmware for the badge comes in. It brings support for Meshtastic proper, as well as longer battery life support for GPS module. To install this firmware you will need to have the ESP-IDF but fortunately there are very comprehensive instructions provided to help you. Under the hood it’s running FreeRTOS.

It’s something which is so often missing with an event badge, any sense of how it might have a life after the event rather than becoming a piece of e-waste. The Communicator badge is such a nice physical design that it obviously has potential, so this firmware unlocks it and gives the badge a use out in the real world. We really like it for this, and we’ll be flashing a few of our badges over to give it a shot shorlty.

If you’re looking to upgrade the hardware on your Communicator, check out the custom RGB keyboard we covered last week.

2026 Green Powered Challenge: Solar-Powered Pollution Monitor

April 24, 2026 by 6 Comments

As we learn more about all the nasty stuff floating in the air, it becomes more compelling to monitor the air for pollution levels. [Aleksei Tertychnyi] does just that with pollutagNode2, a solar-powered pollution sensor.

The device uses a Seeed Studio Wia-E5 module for its built-in LoRa low power long-range communication capabilities. Pair that with a cheap 2 watt solar panel and a Li-ion battery, and you have a monitoring device that can stay up indefinitely — or until harsh weather gets the better of it. Even if the solar panel were to be omitted, a full charge would last you about two weeks!

It comes on an open-hardware PCB; no need for giant wire messes, just solder the solar panel, battery, sensor, and anything else you want onto the convenient pads on the side. It also integrates into the existing sensor community nicely via existing LoRa infrastructure. All this combined makes it easy for anyone to deploy one.

2026 Hackaday Green Powered Challenge

Meshtastic Does More Than Simple Communication

February 22, 2026 by 27 Comments

Meshtastic has been experiencing a bit of a renaissance lately, as the off-grid, long-range radio text messaging protocol gains a ton of new users. It’s been used to create mesh networks in cities, during disasters and protests, in small groups while hiking or camping, and for search and rescue operations. Although it’s connected plenty of people together in all of these ways, [GreatScott!] wanted to put it to work connecting some computing resources instead. He has a garden shed that’s too far for WiFi, so Meshtastic was used to connect it instead.

This isn’t a project to bring broadband Internet out to the shed, though; Meshtastic is much too slow for that. All he really wanted to do here was to implement a basic alarm system that would let him know if someone had broken in. The actual alarm triggering mechanism is an LED emitter-detector pair installed in two bars, one of which sends a 12V signal out if the infrared beam from the other is broken. They’re connected to a Heltec ESP32 LoRa module which is set up to publish messages out on the Meshtastic communications channel. A second module is connected to the WiFi at the house which is communicates with his Home Assistant server.

Integrating Meshtastic devices into Home Assistant can be pretty straightforward thanks to the various integrations already available, but there is some configuration to get these specific modules working as an alarm. One of the pins on the remote module had to be set up to watch the light bar, and although sending the alarm message out when this triggered worked well, the received signal never passed through to Home Assistant until [GreatScott!] switched to using the RadioLib library an an MQTT integration instead. But with perhaps more configuration than he planned for out of the way, [GreatScott!]’s alarm is up and running. Meshtastic projects often balloon into more than we had originally planned though, in more ways than one. You can follow along as our own [Tom Nardi] attempts to connect all of New Jersey with this new protocol.

Continue reading “Meshtastic Does More Than Simple Communication” →

Converting A Nebra Cryptocurrency Miner To A Meshcore Repeater

January 22, 2026 by 6 Comments

After the swivel by Helium Inc. towards simply running distributed WiFi hotspots after for years pushing LoRaWAN nodes, much of the associated hardware became effectively obsolete. This led to quite a few of these Nebra LoRa Miners getting sold off, with the [Buy it Fix it] channel being one of those who sought to give these chunks of IP-67-rated computing hardware a new life.

Originally designed to be part of the Helium Network Token (HNT) cryptocurrency mining operation, with users getting rewarded by having these devices operating, they contain fairly off-the-shelf hardware. As can be glanced from e.g. the Sparkfun product page, it’s basically a Raspberry Pi Compute Module 3+ on a breakout board with a RAK 2287 LoRa module. The idea in the video was to convert it into a Meshcore repeater, which ought to be fairly straightforward, one might think.

Unfortunately the unit came with a dead eMMC chip on the compute module, the LoRa module wasn’t compatible with Meshcore, and the Nebra breakout board only covers the first 24 pins of the standard RPi header on its pin header.

Continue reading “Converting A Nebra Cryptocurrency Miner To A Meshcore Repeater” →